Characterization of bortezomib-adapted I-45 mesothelioma cells

<p>Abstract</p> <p>Background</p> <p>Bortezomib, a proteasome-specific inhibitor, has emerged as a promising cancer therapeutic agent. However, development of resistance to bortezomib may pose a challenge to effective anticancer therapy. Therefore, characterization of cellular mechanisms involved in bortezomib resistance and development of effective strategies to overcome this resistance represent important steps in the advancement of bortezomib-mediated cancer therapy.</p> <p>Results</p> <p>The present study reports the development of I-45-BTZ-R, a bortezomib-resistant cell line, from the bortezomib-sensitive mesothelioma cell line I-45. I-45-BTZ-R cells showed no cross-resistance to the chemotherapeutic drugs cisplatin, 5-fluorouracil, and doxorubicin. Moreover, the bortezomib-adapted I-45-BTZ-R cells had decreased growth kinemics and did not over express proteasome subunit β5 (PSMB5) as compared to parental I-45 cells. I-45-BTZ-R cells and parental I-45 cells showed similar inhibition of proteasome activity, but I-45-BTZ-R cells exhibited much less accumulation of ubiquitinated proteins following exposure to 40 nm bortezomib. Further studies revealed that relatively low doses of bortezomib did not induce an unfolded protein response (UPR) in the bortezomib-adapted cells, while higher doses induced UPR with concomitant cell death, as evidenced by higher expression of the mitochondrial chaperone protein Bip and the endoplasmic reticulum (ER) stress-related pro-apoptotic protein CHOP. In addition, bortezomib exposure did not induce the accumulation of the pro-apoptotic proteins p53, Mcl-1S, and noxa in the bortezomib-adapted cells.</p> <p>Conclusion</p> <p>These results suggest that UPR evasion, together with reduced pro-apoptotic gene induction, accounts for bortezomib resistance in the bortezomib-adapted mesothelioma cell line I-45-BTZ-R.</p

Mapping Brain Response to Pain in Fibromyalgia Patients Using Temporal Analysis of fMRI

Background: Nociceptive stimuli may evoke brain responses longer than the stimulus duration often partially detected by conventional neuroimaging. Fibromyalgia patients typically complain of severe pain from gentle stimuli. We aimed to characterize brain response to painful pressure in fibromyalgia patients by generating activation maps adjusted for the duration of brain responses. Methodology/Principal Findings: Twenty-seven women (mean age: 47.8 years) were assessed with fMRI. The sample included nine fibromyalgia patients and nine healthy subjects who received 4 kg/cm2 of pressure on the thumb. Nine additional control subjects received 6.8 kg/cm2 to match the patients for the severity of perceived pain. Independent Component Analysis characterized the temporal dynamics of the actual brain response to pressure. Statistical parametric maps were estimated using the obtained time courses. Brain response to pressure (18 seconds) consistently exceeded the stimulus application (9 seconds) in somatosensory regions in all groups. fMRI maps following such temporal dynamics showed a complete pain network response (sensory-motor cortices, operculo-insula, cingulate cortex, and basal ganglia) to 4 kg/cm2 of pressure in fibromyalgia patients. In healthy subjects, response to this low intensity pressure involved mainly somatosensory cortices. When matched for perceived pain (6.8 kg/cm2), control subjects showed also comprehensive activation of pain-related regions, but fibromyalgia patients showed significantly larger activation in the anterior insula-basal ganglia complex and the cingulate cortex. Conclusions/Significance: The results suggest that data-driven fMRI assessments may complement conventional neuroimaging for characterizing pain responses and that enhancement of brain activation in fibromyalgia patients may be particularly relevant in emotion-related regions

Mitochondria-localising DNA-binding biscyclometalated phenyltriazole iridium(III) dipyridophenazene complexes: syntheses and cellular imaging properties

Two new biscyclometalated complexes [Ir(ptzR)2(dppz)]+ (dppz = dipyridophenazene; ptzRH = 4-phenyl-1-benzyl-1,2,3-triazole (1+) and 4-phenyl-1-propyl-1,2,3-triazole (2+)) have been prepared. The hexafluorophosphate salts of these complexes have been fully characterized and, in one case, the X-ray structure of a nitrate salt was obtained. The DNA binding properties of the chloride salts of the complexes were investigated, as well as their cellular uptake by A2780 and MCF7 cell lines. Both complexes display an increase in the intensity of phosphorescence upon titration with duplex DNA, indicating the intercalation of the dppz ligand and, given that they are monocations, the complexes exhibit appreciable DNA binding affinity. Optical microscopy studies reveal that both complexes are taken up by live cancer cell lines displaying cytosol based luminescence. Colocalization studies with commercial probes show high Pearson coefficients with mitotracker dyes confirming that the new complexes specifically localize on mitochondria

Thyroid hormones, brain function and cognition

NoIn addition to their role in cellular metabolic activity, thyroid hormones (THs), also regulate neural development; the central nervous system is particularly dependent on TH for normal maturation and function. Specifically, there appears to be extensive inter-reliance between TH and acetylcholine (Ach), nerve growth factor and hippocampal function. These associations led us to investigate the possible effects of thyroxine (L-T4) on performance of a spatial learning task, where cholinergic activity and hippocampal function are known to be important. Groups of rats (n=20) received saline (controls) or L-T4 at 2.5 or 5 mg/kg daily for 4 days as a sub-chronic treatment, or 0, 5 or 10 mg/kg doses administered every third day for 28 days prior to testing as a chronic regimen. Rats were assessed in a watermaze for their ability to find a submerged or visible platform. Forty minutes prior to watermaze testing, half the animals in each group received 1 mg/kg scopolamine to elicit a cognitive deficit. Following testing, rats were decapitated, blood samples taken, and the frontal cortex and hippocampus were dissected out for acetylcholinesterase (AChE) assay. The results showed that L-T4 treatment, administered both sub-chronically and chronically, significantly enhanced the ability of rats to learn a spatial memory task, compared with controls. Moreover, both short-term and long-term L-T4 treatment reduced the cognitive-impairing effects of scopolamine. Improvements in performance were shown to occur alongside significantly increased cholinergic activity in frontal cortex and in the hippocampus of treated animals.These findings demonstrate an augmentative effect of L-T4 upon cognitive function, possibly mediated by an enhancement of cholinergic activity. The results support previous findings of a relationship between L-T4 and acetylcholine, and underscore possible mechanisms by which disorders of thyroid function may be associated with cognitive decline

Gestational stress induces post-partum depression-like behaviour and alters maternal care in rats

NoGestational stress (GS) produces profound behavioural impairments in the offspring and may permanently programme hypothalamic¿pituitary¿adrenal (HPA) axis function. We investigated whether or not GS produced changes in the maternal behaviour of rat dams, and measured depression-like behaviour in the dam, which might contribute to effects in the progeny. We used the Porsolt test, which measures immobility in a forced-swim task, and models depression in rodents, while monitoring maternal care (arched-back nursing, licking/grooming, nesting/grouping pups). Pregnant rats underwent daily restraint stress (1 h/day, days 10¿20 of gestation), or were left undisturbed (control). On post-parturition days 3 and 4, dams were placed into a swim tank, and time spent immobile was measured. GS significantly elevated immobility scores by approximately 25% above control values on the second test day. Maternal behaviours, in particular arched-back nursing and nesting/grouping pups, were reduced in GS dams over post-natal days 1¿10. Adult offspring showed increased immobility in the Porsolt test, and also hypersecreted ACTH and CORT in response to an acute stress challenge. These data show that GS can alter maternal behaviour in mothers, and this might contribute to alterations in the offspring. GS may be an important factor in maternal post-natal depression, which may in turn detrimentally effect the offspring because depressed mothers do not sufficiently care for their offspring

Chronic aspirin ingestion improves spatial learning in adult and aged rats

NoEpidemiological evidence suggests that nonsteroidal, anti-inflammatory drugs (NSAIDs) may retard the progression of Alzheimer's disease (AD). In the present study, we have chronically treated adult (4¿5 months old) and aged (20+ months) rats with water adulterated with aspirin, and examined spatial learning in a swim maze. Adult rats (n=40) and aged rats (n=20) were divided into separate groups assigned to receive either normal drinking water or water with 2 mg/ml of aspirin dissolved in it. For 6 weeks, we monitored daily water and/or drug intake before testing all rats in a standard swim maze over an 8-day period. On average, each rat drank approximately 25 ml of water/day with no apparent control versus aspirin group differences. There was no effect of aspirin in young adult rats except during a visible platform trial where aspirin-treated rats performed better than controls. In contrast, aspirin markedly improved performance in the aged rats during hidden and visible platform trials. Such group differences abated by the eighth test day when all rats performed equally well. The improvements in performance were not correlated with changes in swim speeds indicating that the enhancement was not due to facilitated motor output. These data reveal that a modest, 6-week treatment regimen with aspirin in aged rats is sufficient to induce improvements in both speed of learning and strength of the learned response. We have yet to address the key question as to underlying physiological mechanism(s) that might underpin this augmented cognitive performance. Moreover, it would be useful to ascertain whether or not chronic NSAID treatment might reduce the extent of learning impairments in aged, cognitively impaired animals

Mobile phone use facilitates memory in male, but not female, subjects.

NoIn the present study we report on the effects of mobile phone exposure on short- and long-term memory in male and female subjects. Subjects were university undergraduate students, and consisted of right-handed, males (n = 33) and females (n = 29). Individuals were randomly assigned to one of three experimental conditions: no phone exposure; inactive phone exposure; and active phone exposure. They were provided with a series of words to learn, structured in a two-dimensional shape, and given 3 min to memorise the words. After a 12 min distraction task, they were then asked to draw the shape (spatial) and place the correct words (semantic) into the appropriate boxes. One week later the same subjects were brought back to again redraw the shape and words. Error scores were determined and analysed by non-parametric techniques. The results show that males exposed to an active phone made fewer spatial errors than those exposed to an active phone condition, while females were largely unaffected. These results further indicate that mobile phone exposure has functional consequences for human subjects, and these effects appear to be sex-dependent

Significant Immediate and Long-term Improvement in Quality of Life and Disease Coping in Patients with Vitiligo after Group Climatotherapy at the Dead Sea.

noQuality of life in patients with vitiligo is impaired. This study explored the immediate effect of 20 days of climato­therapy at the Dead Sea on quality of life, coping with the disease, general well-being and individual stress levels in a group of 71 patients with vitiligo and 42 matched controls. The long-term effect was assessed after 12 months in 33/71 patients and 12/42 controls. Study instruments were Dermatology Life Quality Index, Beck Depression Inventory and the Adjustment to Chronic Skin Disorders Questionnaire. Stress measurements were based on cortisol and β-endorphin concentrations in saliva samples. Quality of life was significantly improved at day 20 at the Dead Sea compared with day 1, and this was still significant after 12 months. Moreover, social anxiety/avoidance, anxious-depressive mood and helplessness as measured by the Adjustment to Chronic Skin Disorders Questionnaire were significantly reduced. There was no difference in levels of cortisol and β-endorphin between patients and controls, indicating that stress per se is not a significant contributor in vitiligo. In conclusion, therapy in patient groups offers an effective tool for long-lasting improvement in quality of life and patients’ well-being