Ibuprofen reduces energy expenditure and acute-phase protein production compared with placebo in pancreatic cancer patients.

The aim of this study was to investigate the effect of the cyclo-oxygenase inhibitor ibuprofen on the acute-phase protein response and resting energy expenditure (REE) of weight-losing patients with pancreatic cancer. Patients with irresectable pancreatic cancer (n = 16) were treated with either ibuprofen (1200 mg day-1 for 7 days (n = 10) or placebo (n = 6). A group of 17 age-related non-cancer subjects were also studied. Indirect calorimetry, anthropometry, multifrequency bioelectrical impedence analysis and serum C-reactive protein (CRP) estimation were performed immediately before and after treatment. Before treatment, total REE was significantly elevated in the pancreatic cancer patients compared with healthy controls (1499 +/- 71 vs 1377 +/- 58 kcal) (P < 0.02). Following treatment the mean REE of the ibuprofen group fell significantly (1386 +/- 89 kcal) compared with pretreatment values (1468 +/- 99 kcal) (P < 0.02), whereas no change was observed in the placebo group. Serum CRP concentration was also reduced in the ibuprofen-treated group (pre-ibuprofen, 51 mg l-1; post-ibuprofen, 29 mg l-1; P < 0.05). These results suggest that ibuprofen may have a role in abrogating the catabolic processes which contribute to weight loss in patients with pancreatic cancer

Progressive Neurodegeneration or Endogenous Compensation in an Animal Model of Parkinson's Disease Produced by Decreasing Doses of Alpha-Synuclein

The pathological hallmarks of Parkinson's disease (PD) are degeneration of dopamine (DA) neurons of the substantia nigra (SN) and the presence of alpha-synuclein (α-syn)-rich Lewy bodies in DA cells that remain. To model these aspects of the disease, we previously showed that high titer (5.1×10exp12 gp/ml) AAV1/2 driven expression of A53T α-syn in the SN of rats caused nigrostriatal pathology including a loss of DA neurons, but also with toxicity in the GFP control group. In the current study, we evaluate the effects of two lower titers by dilution of the vector (1∶3 [1.7×10exp12] and 1∶10 [5.1×10exp11]) to define a concentration that produced pathology specific for α-syn. In GFP and empty vector groups there were no behavioural or post-mortem changes at 3 or 6 weeks post-administration at either vector dose. Dilution of the AAV1/2 A53T α-syn (1∶3) produced significant paw use asymmetry, reductions in striatal tyrosine hydroxylase (TH), and increases in DA turnover at 3 weeks in the absence of overt pathology. By 6 weeks greater evidence of pathology was observed and included, reductions in SN DA neurons, striatal DA, TH and DA-transporter, along with a sustained behavioural deficit. In contrast, the 1∶10 AAV1/2 A53T α-syn treated animals showed normalization between 3 and 6 weeks in paw use asymmetry, reductions in striatal TH, and increased DA turnover. Progression of dopaminergic deficits using the 1∶3 titer of AAV1/2 A53Tα-syn provides a platform for evaluating treatments directed at preventing and/or reversing synucleinopathy. Use of the 1∶10 titer of AAV1/2 A53T α-syn provides an opportunity to study mechanisms of endogenous compensation. Furthermore, these data highlight the need to characterize the titer of vector being utilized, when using AAV to express pathogenic proteins and model disease process, to avoid producing non-specific effects

Stereotaxical Infusion of Rotenone: A Reliable Rodent Model for Parkinson's Disease

A clinically-related animal model of Parkinson's disease (PD) may enable the elucidation of the etiology of the disease and assist the development of medications. However, none of the current neurotoxin-based models recapitulates the main clinical features of the disease or the pathological hallmarks, such as dopamine (DA) neuron specificity of degeneration and Lewy body formation, which limits the use of these models in PD research. To overcome these limitations, we developed a rat model by stereotaxically (ST) infusing small doses of the mitochondrial complex-I inhibitor, rotenone, into two brain sites: the right ventral tegmental area and the substantia nigra. Four weeks after ST rotenone administration, tyrosine hydroxylase (TH) immunoreactivity in the infusion side decreased by 43.7%, in contrast to a 75.8% decrease observed in rats treated systemically with rotenone (SYS). The rotenone infusion also reduced the DA content, the glutathione and superoxide dismutase activities, and induced alpha-synuclein expression, when compared to the contralateral side. This ST model displays neither peripheral toxicity or mortality and has a high success rate. This rotenone-based ST model thus recapitulates the slow and specific loss of DA neurons and better mimics the clinical features of idiopathic PD, representing a reliable and more clinically-related model for PD research

Ventral tegmental area dopamine neurons are resistant to human mutant alpha-synuclein overexpression

Parkinson's disease (PD) is characterized by the formation of intracytoplasmic inclusions, which contain alpha-synuclein (alpha-syn) protein. While most profound neurodegeneration is seen in the dopamine (DA) synthesizing neurons located in the ventral midbrain, it is unclear why some DA cell groups are more susceptible than others. In the midbrain, the degeneration of the substantia nigra (SN) DA neurons is severe, whereas the involvement of the ventral tegmental area (VTA) neurons is relatively spared. In the present study, we overexpressed human A53T alpha-syn in the VTA neurons and found that A53T toxicity did not affect their survival. There was, however, a mild functional impairment seen as altered open field locomotor activity. Overexpression of A53T in the SN, on the other hand, led to profound cell loss. These results suggest that the selective susceptibility of nigral DA neurons is at least in part associated with factor(s) involved in handling of alpha-syn that is not shared by the VTA neurons. Secondly, these results highlight the fact that impaired but surviving neurons can have a substantial impact on DA-dependent behavior and should therefore be considered as a critical part of animal models where novel therapeutic interventions are tested

Functional convergence of dopaminergic and cholinergic input is critical for hippocampus-dependent working memory

Although Parkinson\u2019s disease is a movement disorder, in many patients cognitive dysfunction is an important clinical sign. It is not yet clear whether this is attributable solely to a decrease in dopamine levels, or whether other neurotransmitter systems might be involved as well. In the present study, the importance of the mesocorticolimbic dopamine pathway and a possible convergence with forebrain cholinergic projections to neocortex and hippocampus in the regulation of learning and memory abilities were investigated by using specific lesion paradigms in one or both systems. Lesioning of dopaminergic neurons in the ventral tegmental area resulted in an impaired performance in the reference memory task, whereas the execution of the working memory tasks appeared to be unaffected in the Morris water maze. Analysis of the swim paths revealed that the dopamine-depleted animals were capable of adapting a search strategy on a given testing day but failed to transfer this information to the next day, suggesting a deficit in information storage and/or recall. In contrast, cholinergic lesions alone were without effect in all test paradigms. However, when both dopamine and acetylcholine were depleted, animals were also impaired in the working memory task, indicating that a functional convergence of the inputs from these systems was critical for acquisition of spatial memory. Interestingly, such an additional acquisition deficit appeared only after hippocam- pal cholinergic depletion regardless of a concurrent disruption of basalocortical cholinergic afferents. Thus, further analyses of cholin- ergic alterations may prove useful in better understanding the cognitive symptoms in Parkinson\u2019s disease

The effects of macrophage migratory inhibitory factor on acute-phase protein production in primary human hepatocytes

Macrophage inhibitory factor (MIF) is a pituitary peptide released during the physiological stress response, a T-cell product secreted during the antigen-specific response and a pro-inflammatory macrophage cytokine secreted after LPS stimulation. It has become apparent that MIF is central to the regulation of the inflammatory response and is implicated in the pathogenesis of a variety of acute and chronic inflammatory conditions. This is, at least in part, due to the apparent counter-regulation of the anti-inflammatory actions of glucocorticoids, including the reversal of glucocorticoid-mediated IL-6 release inhibition. This study examines the effect of recombinant MIF on regulation of the acute phase response in isolated human hepatocytes. MIF alone increased C-reactive protein (CRP) release in a dose-dependent manner < or = 0.1 ng/ml after which the effects of MIF were attenuated. In combination with IL-6 both CRP and and alpha-1-antichymotrypsin (ACT) release were increased above levels found with either IL-6 or MIF treatment alone. Dexamethasone attenuated the effects of MIF upon CRP production but increased the MIF stimulated release of ACT. The study demonstrates that the effects of MIF upon the acute phase response are complex and can differentially modulate the production of acute phase proteins depending on the presence of other factors

Vasculitis and antineutrophil cytoplasmic autoantibodies associated with propylthiouracil therapy

Vasculitis is a rare complication of propylthiouracil therapy. Antineutrophil cytoplasmic antibodies (ANCA) have been described in association with several vasculitic disorders. We report detection of ANCA against human neutrophil elastase, proteinase 3, and myeloperoxidase in serum from six patients who developed evidence of vasculitis during propylthiouracil treatment of hyperthyroidism. On withdrawal of the drug ANCA concentrations fell and clinical symptoms resolved completely