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OBJECTIVE We have previously shown that inhibition of phosphodiesterase-4(PDE4)protects against neuronal damage in models of Parkinson's dis-ease(PD).However,the mechanisms have not yet been completely revealed.Here we aimed to elucidate the pharmacological effects and mechanisms of action of rof-lupram(ROF),an novel PDE4 inhibitor,in experimen-tal models of PD.METHODS The survival rate,apopto-sis rate and toxicity level of SH-SY5Y cells were deter-mined by MTT,flow cytometry and lactate dehydroge-nase detection kit.At the same time,LYT staining was used to detect the changes of lysosome fluorescence intensity:Western blotting was used to detect the changes of lysosome associated proteins,Sirtuin1 and α-Syn;NAD/NADH assay kit was used to determine the change of NAD content.To explore whether SIRT1 inhibitor(EX527)and lysosomal inhibitor could block the effect of ROF.In addition,ROT was used to stimulate C57BL/6J mice to construct a mouse model of PD to verify the effect and mechanism of ROF.The changes of motor function were evaluated by behavioral experiments(pole climb-ing,bar rotating and balance beam experiments).Super-oxide dismutase kit and Western blotting were used to detect the changes of SOD activity and expression of related proteins in substantia nigra.RESULTS We showed that pretreatment with ROF significantly attenu-ated cell apoptosis in ROT-treated SH-SY5Y cells.Fur-thermore,ROF significantly enhanced the lysosomal function,as evidenced by the increased levels of mature cathepsin D(CTSD)and lysosomal-associated mem-brane protein 1(LAMP1)through increasing NAD+/NADH and the expression of sirtuin 1(SIRT1).Pretreatment with an SIRT1 inhibitor selisistat(SELI,10 μ mol·L-1)attenuated the neuroprotection of ROF,and ROF-increased expression levels of LAMP1 and mature CTSD.Moreover,inhibition of CTSD by pepstatin A(20 μmol·L-1)attenuated the protective effects of ROF.In vivo study was conducted in mice exposed to ROT(10 mg·kg-1·d-1,ig)for six weeks;then,ROT-treated mice received ROF(0.5,1 and 2 mg·kg-1·d-1,ig)for four weeks.ROF significantly ameliorated motor deficits,which was accompanied by increased expression levels of tyro-sine hydroxylase,SIRT1,mature CTSD,and LAMP1 in the substantia nigra pars compacta.CONCLUSION Taken together,these results demonstrate that ROF exerts a neuroprotective action in PD models.The mech-anisms underlying ROF neuroprotective effects appear to be associated with NAD+/SIRT1-dependent activation of lysosomal function.
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OBJECTIVE To investigate the role of PDE4 inhibition in astrocyte swelling caused by cerebral ischemic/reperfusion(I/R)injury and the molecular mech-anisms.METHODS SD rats were subjected to 2 h of focal cerebral ischemia induced by middle cerebral artery occlusion/reperfusion(MCAO/R).Roflumilast(Roflu)was intraperitoneally injected 2 h after MCAO.At 24 h after reperfusion,a high-resolution MRI was performed and using the wet-dry weighting method to measure the water content.The oxygen-glucose deprivation/reoxygenation(OGD/R)model was established in primary astrocytes for 2 h.After 24 h of reoxygenation,CellMask? plasma membrane stain was used to label the plasma membrane to calculate cell volume.The protein expressions insides astrocytes and penumbra were detected by Western blot-ting.To investigate the role of Akt/FoxO3a in mediating the effect of Roflu on the expression of AQP4.The astro-cytes were treated with an Akt inhibitor MK2206 before treatment with Roflu and the activation of Akt,the expres-sion of AQP4 and cell volume were determined as described above.In addition,an IL-1β-stimulated cell model was established in astrocytes,the expression of AQP4 and the activation of Akt/FoxO3a were detected by Western blotting.The change of AQP4 expression inside astrocytes and penumbra were visualized by immunofluo-rescence staining.RESULTS Roflu reduced MCAO/R-induced water contents,the expression of AQP4 and the phsophorylation of Akt and FoxO3a in the brains of MCAO/R rats.Inhibition of PDE4 decreased the cell volume and the expression of AQP4 in primary astro-cytes subjected to OGD/R.PDE4 inhibition activated Akt/FoxO3a,and inhibition of Akt by MK2206 blocked the protective effect of Roflu against OGD/R induced astro-cyte swelling.PDE4B knocking down reduced the expres-sion of AQP4,while PDE4B overexpression reversed the effect of PDE4B siRNA in astrocytes.Roflu exert-ed similar protective effect in IL-1β-cultured astrocytes,and importantly overexpression of FoxO3a remarkably increased the expression of AQP4 in IL-1β-stimulated astrocytes.CONCLUSION Our findings indicate that PDE4 inhibition limits I/R-induced brain edema and astro-cyte swelling via the Akt/FoxO3a/AQP4 pathway.PDE4 inhibition is a promising strategy for the treatment of brain edema after I/R injury.
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Objective To develop an HPLC-MS/MS method for simultaneous determination of xylazine and 2,6-xylidine in body fluid samples.Methods The samples were extracted by HLB SPE,separated by Waters Atlantis dC18 chromatographiccolumn,and then detected in the MRM scan ion mode under positive ionization condition.Results The recoveryrates of this method were between 70.5％ and 79.8％ with the range of RSD rfrom8.2％ to 10.5％.The limits of detection ofxylazine and 2,6-xylidine in blood and urine samples were 0.4 and 0.3 ng/mL,and the limits of quantitation were 1.2 and 1.0 ng/mL,respectively.Conclusion This method is of high sensitivity,good specificity and good reproducibility,and thus could besuitable for accurate quantification of xylazine in blood and urine samples.
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Alzheimer′s disease(AD)is one of the most common causes of cognitive impairment.“Aβhypothesis”and“tau protein aggregation hypothesis”are two representative hypotheses in relation to AD pathology. But recently,therapeutic strategy target?ing on reducing Aβdeposition failed in clinical trials. On the other hand,as the phosphorylation of tau protein is regulated by multiple upstream kinases,inhibition of a single kinase usually cannot effectively suppress the aggregation of the tau. While blocking multiple kinases at the same time will produce serious side effects. Currently,targeting on Aβand tau protein get into awkward situations. In view of this,researchers are looking for new drug targets for improving cognitive function. Phosphodiesterase 4(PDE4 4)is an enzyme responsible for the hydrolysis of cAMP in the body. There are four subtypes for PDE4,and PDE4A,B and D are highly expressed in the central nervous system. Inhibition of PDE4 causes activation of cAMP/PKA/CREB/BDNF signal pathway,which is beneficial for the strengthening and consolidation of learning and memory. This review will focus on the most recent evidence regarding the role of PDE4 in learning and memory.
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Depression is a common mental disorder,characterized by long-lasting sadness,loss of interest and desperation. People with depressive disorder have a high suicide risk,so depression has become a serious threat to an individual′s health and life. Currently,development of anti-depressants is largely limited due to the complexity of this disorder. Clinically available antidepressants are still unable to meet the needs of patients because of both low efficacy and side effects. Recently,with the in-depth study,substan?tial evidence reveals that abnormalities in synaptic plasticity play important roles during the process of depression. Improving synaptic plasticity will be beneficial to ameliorating depressive symptoms and the accompanying cognitive dysfunction. Here ,we review the role of synaptic plasticity during the development of depression and its association with brain-derived neurotrophic factor,astrocytes and microglia.
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Aim To investigate the effect of the total flaconoids extracted from Xiaobuxin-Tan g ( XBXT-2 ) on the hyperactivity of hypothalamic-pituitary-adrenal axis in mouse learned helplessness model. Methods Learned helplessness was induced by inescapable foot shock stress over 1h session for 5 days. After screen-ing, we divided learned helplessness mice into five groups:IS, inescapable shock;Dlx, dulxetine(20 mg ·kg-1);XBXT-2(25,50 mg·kg-1). Latency to es-cape shocks and escape failure had been recorded. During the test, Dlx(20 mg·kg-1 ) and XBXT-2(25, 50 mg·kg-1 ) were administered intragastrically once daily for four days. Serum corticosterone level and ad-renocorticotropic hormone ( ACTH ) level were meas-ured by ELISA, and expression of glucocorticoids re-ceptor ( GR) α/β and brain-derived neurotrophic fac-tor ( BDNF ) in hippocampus was determined using Western blot method. Results XBXT-2 (25,50 mg· kg-1 ) or duloxetine treatment showed antidepressant effect in mouse learned helplessness model, as demon-strated by the decreased escape failure and escape la-tency. Our ELISA results showed that XBXT-2 or du-loxetine significantly decreased serum corticosterone level and its upstream stress hormone ACTH level in learned helplessness mice. Furthermore, Western blot result demonstrated XBXT-2 treatment increased GRs and BDNF expression in hippocampus. Conclusions XBXT-2 produces significant antidepressant effect on learned helplessness mice. In addition, the modulation of HPA axis produced by XBXT-2 may be important mechanism underlying its antidepressant-like effect in mouse learned helplessness model.
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Objective To investigate the effect of metformin ( MET) on learning and memory behavior in HFD-induced insulin-resistant rats.Methods Thirty male Sprague-Dawley (SD) rats were divided into three groups to receive either a normal diet (Control group) or a high-fat diet (two HFD groups) for four weeks(HFD+MET).From two HFD groups, one received vehicle ( HFD group ) alone and other MET administration ( HFD+MET group ) .MET was dissolved in drinking water at a concentration of 2 mg/ml.All rats were subjected to the glucose tolerance test ( GTT) and behavioral tests using the elevated plus maze ( EPM ) , open field test ( OFT ) , Morris water maze ( MWM ) test and the step-through passive avoidance test ( PA) after four-week consecutive MET treatment .Blood samples were collected for determination of glucose. Results MET attenuated the glucose resistant condition and improved cognitive behavior in MWM and PA, vs the HFD group. Conclusion MET can improve the impaired learning and memory behavior in HFD-induced insulin-resistant rats.
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Alzheimer's disease(AD)is a progressive neurodegenerative disease characterized by cognition impairment and behavioral abnormalities.While the mechanisms involved in AD remain unclear,various hypotheses have been proposed regarding pathogenesis of AD,among which the oxidative stress hypothesis has attracted more and more attention.In the present article,the relationship between oxidative stress and AD is reviewed,including sources of neuronal oxygen radical generation,the link of oxidative stress to pathogenesis of AD,preclinical and clinical studies of AD,therapeutic effects of antioxidants and phosphodiesterase inhibitors on AD.
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Traditionally,the nellrorl of central nervous system has been regarded as lack of regeneration capability.Recent studies have found that cerebral ischemia may activate neurogenesis in brains of adult mammals,and bring new hope for neural repair after ischemic brain injury.It is very necessary to fully understand the site of neurogenesis,process and neurogenesis after cerebral ischemia and its regulation mechanisms in adult mammals.
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BACKGROUND: The upward attack of drug-heat is a special type of syndromes of coexistence of cold and heat, it influence the treatment and conversion of the primary disease.OBJECTIVE: To investigate the pathophysiological basis of upward attack of drug-heat.DESIGN: A randomized and controlled observation. SETTING: Department of Traditional Chinese Medicine (TCM) of the People' s Central Hospital of Huizhou City.PARTICIPANTS: Totally 427 patients with cold syndrome, visiting on Department of TCM of the People's Central Hospital of Huizhou City from January 1996 to December 2001, were given warm-heat remedy. Among them 66 cases, 30 males and 36 females, got upward attack of drug-heat during the process of treatment were enrolled. All these subjects, according to their visiting order, at a ratio of 2:1, were chosen as treatment group (44 cases) and control group (22 cases).METHODS: For the patients in treatment group: Rhubarb 6 g was added boiling water 100 mL and soaked for 8 minutes, then the soaking solution was given to the patients, once a day, for 3 days successively. For patients in control group: Table salt 6 g was added boiling water 100 mL for soaking for 8 minutes, after the salt was completely dissolved, the solution was given to the patients, once a day for 3 days successively. The patients of the two groups were at the same time given remedy to treat cold syndrome. The changes of free triiodothyronine (FT3), free thyronine (FT4), high sensitizing thyroid-stimulating hormone (HS-TSH) and cortisol of the patients were detected before and after administration of warm-heat remedy, before and after medication with rhubarb. MAIN OUTCOME MEASURES: ① The changes of the relevant hormones of the patients with upward attack of drug-heat before and after ad ministration of warm-heat remedy. ② The changes of the relevant hormones of the patients with upward attack of drug-heat before and after ad ministration of rhubarb. ③ Comparison of the therapeutic effects in the two groups.RESULTS: All 66 patients involved entered the final result analysis. ①The changes of the relevant hormones of the patients with upward attack of drug-heat before and after administration of warm-heat remedy: FT3 and FT4 were decreased as compared with those before treatment [(2.51±1.20),(6.50±2.30); (10.01±3.21), (15.50±6.31) pmol/L], but HS-TSH and cortisol were increased as compared with those before treatment [(8.25 ±3.75),(4.11±1.75) mU/L; (0.56±0.17), (0.43±0.10) μmol/L]. ② The changes of the relevant hormones of the patients with upward attack of drug-heat before and after administration of rhubarb: FT3 and FT4 ywere increased as compared with those before treatment[(4.71 ±1.56), (2.45±1.25); (14.21 ±4.61),(10.21±3.52) pmol/L], but HS-TSH and cortisol were decreased as compared with those before treatment [(6.24±2.25), (8.35±3.51) mU/L; (0.48±0.10),(0.60±0.17) μmol/L]. ③ Comparison of the therapeutic effects in the two groups: The rate of excellenly effect in treatment group was obviously higher than that in control group (33%, 5%).CONCLUSION: The pathophysiological basis of upward attack of drug heat is stress state of the body, the secretions of the pituitary-thyroid axis play a role of physiological protection, the adrenocortical function is hyperactive, and rhubarb can control this stress state through inhibiting the metabolism of the body.
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OBJECTIVE: To observe the effects of ginkgolide (GL) on the cerebral blood flow in dogs. METHODS: Dogs anesthetized with sodium pentobarbital were randomly divided into 5 groups, with 4 dogs in each group. Ginkgolide of 4.86, 14.6 and 43.7 mg/kg and Xingling Granule of 0.22 g/kg were administered by gavage to the dogs in each of 4 groups. The dogs in the other group were administered with edible oil (1 ml/kg) as control group. The cerebral blood flow, systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and electro-cardiogram of the dogs were measured at different times after the administration. RESULTS: Ginkgolide of 4.86, 14.6 and 43.7 mg/kg had no obvious effects on the blood pressure and the heart rate. Ginkgolide of 14.6 and 43.7 mg/kg increased the cerebral blood flow 90 minutes after administration, and ginkgolide of 43.7 mg/kg obviously decreased the cerebral vascular resistance 150 minutes after administration. CONCLUSION: Ginkgolide can increase the cerebral blood flow and decrease the cerebral vascular resistance, and it has no obvious effects on blood pressure and heart rate in dogs.
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Objective To investigate the effect of bevacizumab on apoptosis of drug resistant nasopharyngeal carcinoma(NPC) cells in vitro.Methods The human nasopharyngeal carcinoma(NPC) cell line CNE2 and its cisplatin-resistant CNE2/DDP cells were treated with bevacizumab and DDP in various concentrations.The lethal effects of the both drugs and the apoptosis rates on CNE2/DDP cells were then measured separately with MTT assay and flow cytometry,the mRNA expressions of Bcl-2 and Bax in CNE2,CNE2/DDP and CNE2/DDP/Bev cells were detected with semi-quantitative RT-PCR.Results The killing rate in 10?g/ml bevacizumab group was similar to that of blank group(0.0?4.1% vs.5.2?4.3%,P=0.180),while the rates of combination of 10?g/ml bevacizumab and DDP(0.1?g/ml and 0.2?g/ml,separately) were higher than that of using DDP only(42.3?6.5% vs.34.4?5.4%,P=0.041;62.6?5.5% vs.50.0?5.9%,P=0.009).The apoptotic rate of CNE2/DDP,which was caused by combining 0.1?g/ml DDP and 10?g/ml bevacizumab,was much higher than what was produced by DDP alone(87.29?3.38% vs.50.58?8.83%,P=0.049).By means of semi-quantitative RT-PCR assay,the expressions of Bcl-2 mRNA in CNE2,CNE2/DDP and CNE2/DDP/Bev cells were 0.613,0.952 and 0.135,respectively.Meanwhile,the expressions of Bax mRNA were 0.665,0.387 and 1.751,separately.Conclusion Bevacizumab can greatly increase the drug sensitivity of CNE2/DDP cells to DDP;apoptosis is inhibited in MDR cells,but it can be promoted by bevacizumab.
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Cell adhesion molecules (CAMs) are involved in glycoproteins expressed on cell surfaces which play an essential role in clinical disorders. At present, there are several groups of anti inflammatory drugs interfere with the expression of CAMs either directly or indirectly. This paper reviews the study of recent finding pharmacological agents associated with CAMs.
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AIM: To explore the effects of Compound Yi-Zhi (YZC) on learning and memory capacity and free radical metabolism in D-galactose induced mice dementia model. METHODS: The mice dementia model was induced by a daily D-galactose 0.15 g?kg -1 sc for 45 d and after 5 d D-galactose injection, the mice were treated with three doses of YZC once a day for 40 d. In order to find out the influence of YZC on the models learning and memory capability and free radical metabolism system, Y-maze test was introduced for the former and superoxide dismutase (SOD) and malondialdehyde (MDA) tests for the latter. RESULTS: Compared with the D-galactose model group, three doses of YZC administration ( 0.108, 0.217, 0.433 g?kg -1) were all shown to significantly reduced the times of learning/memory in Y-maze test from 31.35? 8.97/ 17.12? 5.57 to 19.67? 8.07/ 11.27? 6.65, to 14.00? 6.84/ 8.29? 5.95, and to 11.41? 5.99/ 6.24? 4.97, respectively. For SOD, the administrations of 0.108 and 0.433 g?kg -1 YZC could increase the activity of SOD from 17.69? 3.14 to 26.94? 4.46, and to 21.33? 3.63 nU?mg -1 pro. While for MDA, all the three doses of YZC could decrease the level of MDA from 4.08? 0.88 to 2.82? 0.75, to 2.10? 0.42, and to 2.35? 0.39 nmol?mg -1 pro in the mice brain tissue, respectively. CONCLUSION: YZC can improve the D-galactose induced learning and memory dysfunction, and the action may be related to the improvement of antioxidase activity in the model mice brains.
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This paper described the progress in therapeutics of drug dependence by opioids, involved in usages of opiate receptor agitations, non-opiate receptor agitations, non-drug treatment, and immunosuppressive therapy.
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AIM: To study the effects of the composite lactogenic decoction (CLD) on milk secretion of hypoprolactinemia induced by L dopa in rats. METHODS: The models of hypoprolactinemia were established with L dopa in rats. The weight of young rats was recorded during 15 days. Levels of serum prolactin were detected by ELISA and the mammary gland histology was observed by electron microscop. RESULTS: The administration of CLD (3, 6 and 20 g?kg -1 ) by the way of ig increased serum prolactin (PRL) level significantly (P
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Object To investigate the nootropic activity of emodin 8 O ? D glucopyranoside, the active principle of Radix Polygoni Multiflori Preparata(PMEG), and its mechanism of action Methods Nootropic activity was evaluated with step down test of mice, and its nootropic mechanism studied by its antiacetylcholinesterase (anti AchE) effect on mice brain in vivo and in vitro as determined by pectrophotometry Results PMEG (ig) significantly improved the learning and memory of both normal and intelectual deficit mice induced by scopolamine PMEG showed dose dependent inhibition of AchE, and the antiacetylcholinesterase effect is reversible both in vivo and in vitro In acute experiment, the half recovery time of AchE is 115 min, and 165 min in chronic experiment Conclusion PMEG showed good nootropic activity, and it is a reversible AchE inhibitor
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AIM: To study the therapeutical effects of salvianolic acid B (Sal B) on myocardial infarction(MI) in dogs. METHODS : The models of myocardial infarction were produced by ligation of the left anterior descending (LAD) coronary artery in the anaesthetized dogs. The extent of myocardial ischemia was detected by epicardial-electrocardiogram and the extent of infarction was determhled by N-BT staining method. The parameter of lactate dehydrogenase was determined in the serums of dogs. RESULTS : It was indicated that the adminstration of Sal B(1、3 and 10mg/kg) by the way of intravenous injection reduced the extent of myocardial infarction (N-ST) ( P
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AIM:To investigate the effects of rolipram on the ability of learning and memory and the activity of PDE4 in hippocampus following the focal brain injury induced by ischemia-reperfusion in rats.METHODS:The cerebral ischemia-reperfusion injury model was made by middle cerebral artery occlusion(MCAO) in rats.The rats were randomly divided into sham-operated group,model group,and rolipram group.Rolipram was administered once a day(1 mg/kg,ip) from 6 h after the onset of the operation for 2 weeks.Then the learning and memory abilities were tested after Morris water maze and step-though training.The activity of PDE4 in hippocampus was evaluated by HPLC.RESULTS:In the Morris water maze test,compared to sham-operated group,the platform-finding time and swimming distance in model group were significantly longer(P
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Aim To investigate the effects of anti-morphine vaccines on pharmacological actions of morphine in mice.Methods Morphine-6-succinyl and morphine were conjugated respectively with Blue Carrier(BC) in the presence of carbodi-imide.After being immunized with both vaccines(M-BC,M-6-S-BC),the withdrawal syndrome and the abirritation were observed in mice.Results The withdrawal syndrome of the immune mice with M-6-S-BC and M-BC vaccines were reduced markedly compared with the model group,the skipping times were decreased and the latency was longer(P