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Background and Purpose: Neuropathic pain affects millions of patients, but there are currently few viable therapeutic options available. Microtubule affinity‐regulating kinases (MARKs) regulate the dynamics of microtubules and participate in synaptic remodelling. It is unclear whether these changes are involved in the central sensitization of neuropathic pain. This study examined the role of MARK1 or MARK2 in regulating neurosynaptic plasticity induced by neuropathic pain. Experimental Approach: A rat spinal nerve ligation (SNL) model was established to induce neuropathic pain. The role of MARKs in nociceptive regulation was assessed by genetically knocking down MARK1 or MARK2 in amygdala and systemic administration of PCC0105003, a novel small molecule MARK inhibitor. Cognitive function, anxiety‐like behaviours and motor coordination capability were also examined in SNL rats. Synaptic remodelling‐associated signalling changes were detected with electrophysiological recording, Golgi‐Cox staining, western blotting and qRT‐PCR. Key Results: MARK1 and MARK2 expression levels in amygdala and spinal dorsal horn were elevated in SNL rats. MARK1 or MARK2 knockdown in amygdala and PCC0105003 treatment partially attenuated pain‐like behaviours along with improving cognitive deficit, anxiogenic‐like behaviours and motor coordination in SNL rats. Inhibition of MARKs signalling reversed synaptic plasticity at the functional and structural levels by suppressing NR2B/GluR1 and EB3/Drebrin signalling pathways both in amygdala and spinal dorsal horn. Conclusion and Implications: These results suggest that MARKs‐mediated synaptic remodelling plays a key role in the pathogenesis of neuropathic pain and that pharmacological inhibitors of MARKs such as PCC0105003 could represent a novel therapeutic strategy for the management of neuropathic pain. [ABSTRACT FROM AUTHOR]

Background: Poor sleep is often associated with a series of health problems in patients with chronic obstructive pulmonary disease (COPD), but the relationship between sleep quality and functional exercise capacity has not been previously investigated. Aims: To evaluate the relationship between quality of sleep and functional exercise capacity in clinically stable COPD. Methods: One hundred three consecutive subjects with stable COPD were recruited. The subjects were assessed with the Pittsburgh Sleep Quality Index (PSQI) and divided into poor sleep group (PSQI >5) and good sleep group (PSQI ≤5). Subjects were also assessed with spirometry, 6-min walk distance (6MWD), oxygen saturation (SγO2), the Epworth Sleepiness Scale, Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, COPD Assessment Test (CAT), Modified Medical Research Council dyspnea scale and quadriceps muscle function. Results: Poor sleep was present in 43.69% of the patients with COPD. Subjects with poor sleep had shorter 6MWD (t = -3.588, P < 0.001), greater age (t = 2.519, P = 0.013), worse quality of life (t = 5.487, P < 0.001) and more depression (t = 6.576, P < 0.001) or anxiety (t = 4.245, P < 0.001) symptoms. 6MWD showed significant negative correlations with the PSQI global score (r = -0.373, P < 0.001). Multiple stepwise regresion analysis showed that PSQI global score was an independent psychological predictor of 6MWD, and 6MWD was the only physical predictor of PSQI total score in patients with COPD. Conclusion: There is a close relationship between sleep quality and functional exercise capacity in patients with COPD. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the efficacy of cornin, an iridoid glycoside, in an experimental cerebral ischemia induced by middle cerebral artery occlusion (MCAO) and reperfusion (I/R), and to elucidate the potential mechanism. Adult male Sprague-Dawley rats were subjected to MCAO for 1 h, then reperfusion for 23 h. Behavioral tests were used to evaluate the damage to central nervous system. The cerebral infarct volume and histopathological damage were assessed to evaluate the brain pathophysiological changes. Spectrophotometric assay methods were used to determine the activities of superoxide dismutase (SOD) and glutathione-peroxidase (GPx). Contents of malondialdehyde (MDA), the generation of reactive oxygen species (ROS) as well as respiratory control ratio and respiratory enzymes of the brain mitochondria were also determined. The results showed that cornin significantly decreased neurological deficit scores, and reduced cerebral infarct volume and degenerative neurons. Meanwhile, cornin significantly increased the brain ATP content, improved mitochondrial energy metabolism, inhibited the elevation of MDA content and ROS generation, and attenuated the decrease of SOD and GPx activities in brain mitochondria. These findings indicate that cornin has protective potential against cerebral ischemia injury and its protective effects may be due to amelioration of cerebral mitochondrial function and its antioxidant property. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Dynamic hyperinflation (DH) is a major contributor to exercise limitation in chronic obstructive pulmonary disease (COPD). Therefore, we aimed to elucidate the physiological factors responsible for DH development during the 6-minute walk test (6MWT) in COPD patients and compare ventilatory response to the 6MWT in hyperinflators and non-hyperinflators., Methods: A total of 105 consecutive subjects with stable COPD underwent a 6MWT, and the Borg dyspnea scale, oxygen saturation (SpO2), breathing pattern, and inspiratory capacity (IC) were recorded before and immediately after walking. The change in IC was measured, and subjects were divided into hyperinflators (ΔIC >0.0 L) and non-hyperinflators (ΔIC ≤0.0 L). Spirometry, the Modified Medical Research Council (MMRC) dyspnea scale and St George's Respiratory Questionnaire (SGRQ) were also assessed., Results: DH was present in 66.67% of subjects. ΔIC/IC was significantly and negatively correlated with the small airway function. On multiple stepwise regression analysis forced expiratory flow after exhaling 50% of the forced vital capacity (FEF50%) was the only predictor of ΔIC/IC. Non-hyperinflators had a higher post-walking VT (t=2.419, P=0.017) and post-walking VE (t=2.599, P=0.011) than the hyperinflators did. Age and resting IC were independent predictors of the 6-minute walk distance (6MWD) in hyperinflators., Conclusions: DH was considerably common in subjects with COPD. Small airway function may partly contribute to the DH severity during walking. The ventilator response to the 6MWT differed between hyperinflators and non-hyperinflators. Resting hyperinflation is an important predictor of functional exercise capacity in hyperinflators.

Objective: This meta-analysis was performed to evaluate the efficacy and safety of the addition of tiotropium to standard treatment regimens for inadequately controlled asthma., Methods: A systematic search was made of PubMed, EMBASE, MEDLINE, and CENTRAL databases, and ClinicalTrials.gov, and a hand search of leading respiratory journals. Randomized, double-blind clinical trials on the treatment of inadequately controlled asthma for ≥ 4 weeks with the addition of tiotropium, compared with placebo, were reviewed. Studies were pooled to odds ratio (OR) and weighted mean differences (WMDs), with 95% CI., Results: Six trials met the inclusion criteria. The addition of tiotropium, compared with placebo, significantly improved all spirometric indices, including morning and evening peak expiratory flow (WMD 20.59 L/min, 95% CI 15.36-25.81 L/min, P < .001; and WMD 24.95 L/min, 95% CI 19.22-30.69 L/min, P < .001, respectively), trough and peak FEV1 (WMD 0.13 L, 95% CI 0.09-0.18 L, P < .001; and WMD 0.10 L, 95% CI 0.06-0.14 L, P < .001, respectively), the area under the curve of the first 3 h of FEV1 (WMD 0.13 L, 95% CI 0.08-0.18 L, P < .001), trough and peak FVC (WMD 0.1 L, 95% CI 0.05-0.15 L, P < .001; and WMD 0.08 L, 95% CI 0.04-0.13 L, P < .001, respectively), the area under the curve of the first 3 h of FVC (WMD 0.11 L, 95% CI 0.06-0.15 L, P < .001). The mean change in the 7-point Asthma Control Questionnaire score (WMD -0.12, 95% CI -0.21 to -0.03, P = .01) was markedly lower in tiotropium group, but not clinically important. There were no significant differences in Asthma Quality of Life Questionnaire score (WMD 0.09, 95% CI -0.01 to 0.20, P = .09), night awakenings (WMD 0.00, 95% CI -0.05 to 0.05, P = .99) or rescue medication use (WMD -0.18, 95% CI -0.36 to 0.00, P = .06). No significant increase was noticed in adverse events in the tiotropium group (OR 0.80, 95% CI 0.62-1.03, P = .08)., Conclusions: The addition of tiotropium to standard treatment regimens has significantly improved lung function without increasing adverse events in patients with inadequately controlled asthma. Long-term trials are required to assess the effects of the addition of tiotropium on asthma exacerbations and mortality.

Doxorubicin (DOX) is considered as one of the best antineoplastic agents. However, its clinical use is restricted by its associated cardiotoxicity, which is mediated by the production of reactive oxygen species. In this study, 20(S)-ginsenoside Rh2 (Rh2) was explored whether it had protective effects against DOX-induced cardiotoxicity. In vitro study on H9C2 cell line, as well as in vivo investigation in one mouse and one rat model of DOX-induced cardiomyopathy, was carried out. The results showed that pretreatment with Rh2 significantly increased the viability of DOX-injured H9C2 cells. In the mouse model, Rh2 could suppress the DOX-induced release of the cardiac enzymes into serum and improved the occurred pathological changes through ameliorating the decreased antioxidant biomolecules and the cumulated lipid peroxidation malondialdehyde in heart tissues. In the rat model, Rh2 could attenuate the change of ECG resulting from DOX administration. Furthermore, Rh2 enhanced the antitumor activity of DOX in A549 cells. Our findings thus demonstrated that Rh2 pretreatment could effectively alleviate heart injury induced by DOX, and Rh2 might act as a novel protective agent in the clinical usefulness of DOX.

Astilbin, a flavonoid compound, was isolated from the rhizome of Smilax glabra Roxb. This study was conducted to investigate the efficacy of astilbin on experimental diabetic nephropathy (DN) in vivo and in vitro and its possible mechanisms. Astilbin was added in high glucose stimulated HK-2 cells, streptozotocin-induced experimental DN, randomized to receive intragastric ( I. G.) astilbin to observe its anti-renal lesion effect. Results showed that astilbin inhibited high glucose stimulated HK-2 cell production of transforming growth factor-beta1 (TGF-beta1) and connective tissue growth factor (CTGF) in vitro, especially CTGF; analogic results was also found in vivo. I. G. of astilbin 2.5 mg/kg or 5 mg/kg significantly ameliorated renal function, reduced kidney index, while it increased body weight and survival time in animals. In addition there was no significant difference in blood glucose level between the STZ-treated group and the astilbin groups. Furthermore, astilbin ameliorated the pathological progress of renal morphology. Astilbin can exert an early renal protective role to DN, inhibit production of TGF-beta1 and especially of CTGF. We suggest that astilbin inhibition of CTGF may be a potential target in DN therapy. This work provides the first evidence for astilbin as a new candidate of DN therapeutic medicine., (Georg Thieme Verlag KG Stuttgart, New York.)

Aim: To investigate the protective effect of hydroxysafflor yellow A (HSYA), a soluble element extracted from Carthamus tinctorius L., on focal cerebral ischemia in rats., Methods: Focal cerebral ischemia in male Wistar-Kyoto (WKY) rats were induced by permanent middle cerebral artery occlusion (MCAO). Three doses of 1.5, 3.0 and 6.0 mg x kg(-1) of HSYA were administrated to three groups of rats, separately, via sublingular vein injection 30 min after the onset of ischemia. 24 h after ischemia in rats, neurological deficit scores were evaluated and the infarction area of brain was assessed by quantitative image analysis. The in vitro neuroprotective effect of HSYA was tested in cultured fetal cortical neurons exposed to glutamate and sodium cyanide (NaCN)., Results: HSYA at doses of 3.0 and 6.0 mg x kg(-1) exerted significant neuroprotective effects on rats with focal cerebral ischemic injury as expressed by neurological deficit scores and reduced the infarct area as compared with saline group, and the potency of HSYA at dose of 6.0 mg x kg(-1) was similar to that of 0.2 mg x kg(-1) of nimodipine. In vitro studies, HSYA significantly inhibited neurons damage induced by exposure to glutamate and NaCN in cultured fetal cortical cells., Conclusion: HSYA has potential neuroprotective action against focal cerebral ischemia in rats and cultured rat fetal cortical neurons as well.

Objective: To study the protective effect of ligusticum chuanxiong phthalides on cerebral ischemia in rats and its related mechanism of action., Method: Middle cerebral artery occlusion (MCAO) model, thrombosis formation, platelet aggregation and hemorrheological parameters were measured to evaluate the protective effect of ligusticum chuanxiong phthalides., Result: Ligusticum chuanxiong phthalides could markedly decrease the infarct size and behavior deficits score, inhibit the thrombus formation and platelet aggregation, ameliorate hemorrheological parameters with a dose-dependent manner in rats., Conclusion: Ligusticum chuanxiong phthalides has protective effects on focal cerebral ischemia in rats, and its mechanism may be relevant to its inhibition of platelet-dependent thrombosis and amelioration of hemorrheological parameters.

Aim: To study the effects of hydroxysafflor yellow A (HSYA) on the mitochondrial function of cortex mitochondrial during cerebral ischemia in rats., Methods: Rat focal cerebral ischemia model in rats was established by ligation of middle cerebral central artery. Cortex mitochondria were isolated and prepared for the measurement of membrane fluidity, swelling, respiratory function, activities of mitochondrial respiratory enzymes and superoxide dismutase (SOD), contents of phospholipid, malondial dehyde (MDA) and Ca2+ to evaluate the function of mitochondria., Results: Focal cerebral ischemia resulted in severe neuronal mitochondrial injuries, which could be alleviated by i.v. HSYA (10, 20 mg x kg(-1)), and nimodipine (Nim, 1.0 mg x kg(-1)). The swelling of mitochondria was ameliorated, the decomposability of membrane phospholipid was decreased, the membrane fluidity of mitochondria was increased, HSYA also significantly inhibited the decrease in the activities of respiratory enzymes and SOD of mitochondria, and the increase in MDA and Ca2+ levels caused by cerebral ischemia in rats., Conclusion: HSYA showed a protective action against the cortex mitochondrial injuries in rats induced by cerebral ischemia. The mechanisms may be derived from reducing lipid peroxides, inhibiting Ca2+ overload, scavenging free radicals and improving the energy metabolism.