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Fructose 1,6-bisphosphatase (FBPase) has attracted substantial interest as a target associated with cancer and type 2 diabetes. Herein, we found that disulfiram and its derivatives can potently inhibit FBPase by covalently binding to a new C128 allosteric site distinct from the original C128 site in APO FBPase. Further identification of the allosteric inhibition mechanism reveals that the covalent binding of a fragment of 214 will result in the movement of C128 and the dissociation of helix H4 (123-128), which in turn allows S123 to more easily form new hydrogen bonds with K71 and D74 in helix H3 (69-72), thereby inhibiting FBPase activity. Notably, both disulfiram and 212 might moderately reduce blood glucose output in vivo. Therefore, our current findings not only identify a new covalent allosteric site of FBPase but also establish a structural foundation and provide a promising way for the design of covalent allosteric drugs for glucose reduction.

Background The present study was intended to investigate the protective effect of estradiol against Parkinson’s disease through the use of rotenone-induced neurotoxicity model. Methods To define the effect on the behavioral function, Tail suspension test, morris water maize test and cylinder tests were performed. Several biochemical and histological markers related to Parkinson’s disease was determined in animal and cell culture models. To evaluate the effect of estradiol on the cellular architecture in rotenone-induced brain tissue, the histopathological examination was carried out by using Haemotoxylin and Eosin staining. Moreover, estradiol effect was also been investigated for its protective effect against Parkinson’s disease using cell culture model with use of brain endothelial cells. The flowcytometric analysis was carried out to measure apoptosis in cell culture model. Results The abnormal level of antioxidant enzymes and lipid peroxidation were regulated toward the normal intensity under the influence of estradiol. Furthermore, intracellular ROS level and apoptosis were found to be reduced following estradiol treatment. During the 6-OHDA induced PD, the level of antioxidant marker such as GSH, ROS and TRAP, found to be significantly modulated by the estradiol. Conclusion In view of the above results, it may be suggested that the estradiol may be as a useful therapeutic agent against rotenone-induced neurotoxicity such as Parkinson’s disease.

MicroRNAs (miRNAs/miRs) are a class of conserved non-coding endogenous small regulatory RNAs that regulate target gene expression by binding to the 3′-untranslated region of target mRNAs in a base-pairing manner, resulting in repression of transcription or degradation of target mRNAs. It has been demonstrated previously that the abnormal expression of miRNAs is involved in the carcinogenesis and progression of cervical cancer. The aim of the present study was to investigate the expression, biological functions and underlying molecular mechanisms of miR-195 in cervical cancer. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression level of miR-195 in cervical cancer tissues and cell lines. Following transfection, an MTT assay, cell migration and invasion assays, western blot analysis and a dual-luciferase reporter assay were performed in human cervical cancer cells. In the present study, it was identified that miR-195 was downregulated in cervical cancer tissues and cell lines. Additionally, upregulation of miR-195 and knockdown of hepatoma-derived growth factor (HDGF) inhibited proliferation, migration and invasion of cervical cancer cells. Furthermore, a dual-luciferase reporter assay identified that HDGF was a direct target gene of miR-195. RT-qPCR and western blot analysis demonstrated that miR-195 mimic inhibited HDGF expression at the mRNA and protein levels, whereas miR-195 inhibitor enhanced HDGF expression at the mRNA and protein levels. These results indicated that miR-195 targeted HDGF to inhibit the behavior of tumors in cervical cancer. These results also suggested that miR-195 was a potential therapeutic biomarker of cervical cancer.

Fructose-1,6-bisphosphatase (FBPase), as a key rate-limiting enzyme in the gluconeogenesis (GNG) pathway, represents a practical therapeutic strategy for type 2 diabetes (T2D). Our previous work first identified cysteine residue 128 (C128) was an important allosteric site in the structure of FBPase, while pharmacologically targeting C128 attenuated the catalytic ability of FBPase. Herein, ten approved cysteine covalent drugs were selected for exploring FBPase inhibitory activities, and the alcohol deterrent disulfiram displayed superior inhibitory efficacy among those drugs. Based on the structure of lead compound disulfiram, 58 disulfide-derived compounds were designed and synthesized for investigating FBPase inhibitory activities. Optimal compound 3a exhibited significant FBPase inhibition and glucose-lowering efficacy in vitro and in vivo. Furthermore, 3a covalently modified the C128 site, and then regulated the N125-S124-S123 allosteric pathway of FBPase in mechanism. In summary, 3a has the potential to be a novel FBPase inhibitor for T2D therapy.

Fructose-1, 6-bisphosphatase (FBPase) has been regarded as an attractive drug target to control blood glucose against Type 2 diabetes (T2D). In this study, by using the strategy of pharmacophore-based virtual screening, a novel scaffold inhibitor targeted the AMP allosteric site of human liver FBPase were screened, their inhibitory activities were further tested. The experimental results showed that compound H27 exhibited high inhibitory activities with the IC50 value of 5.3 μM. Therefore, compound H27 was chosen as the probe molecule, it's possible binding conformation targeted into FBPase was identified by using DOX2.0 strategy. The importance of key residues (T27, T31, K112 and R140) in allosteric site of FBPase for the binding inhibitors were validated by mutation experiments. The agreement between theory and experiment suggest that the interactional information of FBPase and inhibitors (H27) were reliable. On basis of these rational interactional information, the compound H29 was further designed to exhibit more potential FBPase inhibition (IC50 = 2.5 μM).

Objectives: This study was intended to investigate whether treatment with resveratrol and melatonin alone or in combination can exert neurorestorative effects in a rat model of vascular dementia. Methods: Briefly, male Wistar rats were subjected to permanent bilateral common carotid artery occlusion (BCCAO) by surgery. After 4 weeks, the cognitive deficits were assessed using the Morris water maze and novel object recognition tests. The biochemical parameters of oxidative stress and inflammation were also assessed. Results: Rats in the BCCAO group showed cognitive deficits, accompanied by oxidonitrosative stress, neuroinflammation, and a reduction in brain-derived neurotrophic factor (BDNF) in the hippocampus region. Moreover, the acetylcholinesterase activity in the hippocampus was found to be increased in the BCCAO group compared to the sham group. The 4-week treatment with melatonin (10 mg/kg) and resveratrol (20 mg/kg) alone and in combination (melatonin 5 mg/kg and reseveratrol 10 mg/kg) caused a significant improvement in the cognitive deficits induced by BCCAO, accompanied by a reversal of oxidonitrosative stress, neuroinflammation, and BDNF depletion in the hippocampus region. Additionally, the treatment with melatonin and resveratrol significantly decreased acetylcholinesterase activity compared to in the BCCAO group. Melatonin and resveratrol ameliorated the BDNF expression of hippocampal protein. Conclusion: These results emphasize that coadministration of melatonin and resveratrol can be beneficial in BCCAO-induced vascular dementia through changes in BDNF expressions.

The influence of the wheel axle bending stiffness to the wheel/rail contact dynamic force and wheelset vertical vibration of the linear metro vehicle on a straight track was investigated. Based on a vehicle dynamic model and two kinds of elastic wheelset models, a comparison was carried out between the wheelset vertical vibration and the wheel/rail vertical force. Simulation results showed that the wheelset vibration and the wheel/rail vertical force of the elastic wheelset model were different with that of the rigid wheelset model; this was due to the BM3000 type wheelset not having high enough bending stiffness. In contrast, the result of the elastic wheelset model of the wheelset of the Beijing metro railway vehicle was quite similar to the results of the rigid model since a larger bending stiffness was used. Consequently, the wheelset vibration and wheel/rail vertical force can be decreased by increasing the wheel axle bending stiffness which will improve wheel/rail dynamic contact conditions. First published online:16 Oct 2013

We recently found that TMPRSS2:ERG fusion genes and PTEN loss, which are common in Western prostate cancers are infrequent in Chinese cases. As previous studies indicated a higher frequency of RAS and BRAF mutation rates in Eastern Asian than in Western prostate cancers and fusion genes involving the RAF family genes BRAF and RAF1 were recently identified in prostate cancer in the American population, we investigated BRAF and RAF1 alterations in Chinese prostate cancer. Using fluorescence in situ hybridization, we found that BRAF was truncated in five of 200 informative Chinese cases (2.5%) and that RAF1 was truncated in three of 204 informative cases (1.5%) and genomic rearrangements of these genes were significantly correlated with high Gleason scores (>7; P < 0.01) and have a trend to appear in high clinical stage disease. A high frequency of BRAF and RAF1 copy number gain was found (29 and 15%, respectively). BRAF copy number gain in Chinese cancers was significantly higher than in UK cases (9.2%)(P < 0.001) and correlated with a number of clinical parameters. High-level expression of BRAF was found by immunohistochemistry in Chinese cancer samples compared with adjacent nonmalignant epithelial cells, which was correlated with high BRAF copy number. We also identified KRAS codon 12 mutations in three of 96 Chinese cases, no BRAF V600E mutations were observed. Our finding suggests that the activation of the RAS/RAF/MEK/ERK pathway may be frequent in Chinese prostate cancer, with RAF gene copy number gain potentially being the main contributor. (c) 2012 Wiley Periodicals, Inc.

Acidosis and alkalosis, associated with metabolic disorders, lead to the pathological changes of cognition and behaviors in clinical practices of neurology and psychology. Cellular mechanisms for these functional disorders in the central nervous system remain unclear. We have investigated the influences of acidosis and alkalosis on the functions of cortical GABAergic neurons. Both acidosis and alkalosis impair the ability of encoding sequential spikes at these GABAergic neurons. The impairments of their spiking are associated with the increases of refractory periods, threshold potential and afterhyperpolarization. Our studies reveal that acidosis and alkalosis impair cortical GABAergic neurons and in turn deteriorate brain functions, in which their final targets may be voltage-gated channels of sodium and potassium.

Spalling like scales of fish will emerge on the connection area between wheel tread and flange of one metro vehicle after it running a period of time on the track. The method of polish the track has not solved the phenomena yet. When wheel is out-of-round, the vertical vibration of the car-body is very big, and the tread must be cut to eliminate the phenomena of vertical vibration big of the car-body, but this method could not solve the problem indeed. These phenomena show that the secondary suspension of the vehicles has not damp function. Both the results of linear frequency analyses and the nonlinear analyses show that the too big stiffness of the traction bar which connected the car-body and the bogie in longitudinal direction has big relation with the vertical dynamic performance of the metro vehicle. From the point of view of the wheel-set longitudinal vibration find that the wheel-set resonance speed is in the usually running speed scope of the metro vehicle and this may be the reason of wheel tread easy splling and out-of-round. The stiffness of the traction bar was depressed by change the two ends to big rubber joints, so the longitudinal force affected by the traction bar is depressed notability, and the vertical dynamic performance of the metro vehicles is then be improved.