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1.
Article in English | MEDLINE | ID: mdl-38804845

ABSTRACT

BACKGROUND AND AIM: Hydronidone (HDD) is a novel pirfenidone derivative developed initially to reduce hepatotoxicity. Our previous studies in animals and humans have demonstrated that HDD treatment effectively attenuates liver fibrosis, yet the underlying mechanism remains unclear. This study aimed to investigate whether HDD exerts its anti-fibrotic effect by inducing apoptosis in activated hepatic stellate cells (aHSCs) through the endoplasmic reticulum stress (ERS)-associated mitochondrial apoptotic pathway. METHODS: The carbon tetrachloride (CCl4)- and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver fibrosis models were used for in vivo studies. In vitro studies were conducted using the human hepatic stellate cell line LX-2. The apoptotic effect of HDD on aHSCs was examined using TUNEL and flow cytometry assays. The small interfering RNA (siRNA) technique was employed to downregulate the expression of interest genes. RESULTS: HDD treatment significantly promoted apoptosis in aHSCs in both the CCl4- and DDC-induced liver fibrosis in mice and LX-2 cells. Mechanistic studies revealed that HDD triggered ERS and subsequently activated the IRE1α-ASK1-JNK pathway. Furthermore, the influx of cytochrome c from the mitochondria into the cytoplasm was increased, leading to mitochondrial dysfunction and ultimately triggering apoptosis in aHSCs. Notably, inhibition of IRE1α or ASK1 by siRNA partially abrogated the pro-apoptotic effect of HDD in aHSCs. CONCLUSIONS: The findings of both in vivo and in vitro studies suggest that HDD induces apoptosis in aHSCs via the ERS-associated mitochondrial apoptotic pathway, potentially contributing to the amelioration of liver fibrosis.

2.
Liver Int ; 43(11): 2523-2537, 2023 11.
Article in English | MEDLINE | ID: mdl-37641479

ABSTRACT

BACKGROUND AND PURPOSE: Liver fibrosis is a wound-healing reaction that eventually leads to cirrhosis. Hydronidone is a new pyridine derivative with the potential to treat liver fibrosis. In this study, we explored the antifibrotic effects of hydronidone and its potential mode of action. METHODS: The anti-hepatic fibrosis effects of hydronidone were studied in carbon tetrachloride (CCl4 )- and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)- induced animal liver fibrosis. The antifibrotic mechanisms of hydronidone were investigated in hepatic stellate cells (HSCs). The antifibrotic effect of hydronidone was further tested after Smad7 knockdown in HSCs in mouse models of fibrosis. RESULTS: In animal models, hydronidone attenuated liver damage and collagen accumulation, and reduced the expression of fibrosis-related genes. Hydronidone decreased the expression of fibrotic genes in HSCs. Impressively, hydronidone significantly upregulated Smad7 expression and promoted the degradation of transforming growth factor ß receptor I (TGFßRI) in HSCs and thus inhibited the TGFß-Smad signalling pathway. Specific knockdown of Smad7 in HSCs in vivo blocked the antifibrotic effect of hydronidone. CONCLUSION: Hydronidone ameliorates liver fibrosis by inhibiting HSCs activation via Smad7-mediated TGFßRI degradation. Hydronidone is a potential drug candidate for the treatment of liver fibrosis.


Subject(s)
Liver Cirrhosis , Signal Transduction , Transforming Growth Factor beta , Animals , Mice , Carbon Tetrachloride/toxicity , Carbon Tetrachloride/metabolism , Hepatic Stellate Cells/drug effects , Hepatic Stellate Cells/metabolism , Liver/pathology , Liver Cirrhosis/drug therapy , Receptor, Transforming Growth Factor-beta Type I , Transforming Growth Factor beta/metabolism , Smad7 Protein/drug effects , Smad7 Protein/metabolism
3.
J Food Sci ; 88(5): 1879-1889, 2023 May.
Article in English | MEDLINE | ID: mdl-37012699

ABSTRACT

There are huge resource reserves of wild edible fungi richer in their varieties in Yunnan Province which is located on plateau of low latitude and possesses unique various climate environments and bigger vegetative cover ratios. Moreover, nutrients and flavor substances in the same or various species of wild edible fungi differ greatly with the influence on different components from habitats and geographic areas. So, 5 common wild edible fungi were collected from different areas in Yunnan Province, and several findings were made from this research. Above all, through the evaluation of amino acids, these 5 fungi met the criteria for ideal protein by WHO/FAO, and the nutritional value of protein was ranked as matsutake > truffle > collybia albuminosa > bolete > chanterelle. Next, after the analysis of taste activity values, the ranking of taste was bolete > collybia albuminosa > truffle > matsutake > chanterelle. Subsequently, the ranking of characters was truffle > collybia albuminosa >bolete > matsutake > chanterelle through principal component analysis. Finally, truffle could be completely divided by Fisher discrimination analysis with a bigger difference from others, main in ash, protein, sugar, and polysaccharide, meanwhile, truffle and bolete could be completely divided by orthogonal projections to latent structures discrimination analysis, main in protein, crude fiber, fat, and amino acid. So, there was a more conspicuous difference in nutrients among fungi, through which nutrients combined with multivariate statistics analysis made possible the correct differentiation of small range categories in wild edible fungi, and the correct classification of small range of them could effectively be realized.


Subject(s)
Agaricales , China , Agaricales/chemistry , Amino Acids , Nutritive Value
4.
Chron Respir Dis ; 19: 14799731221108516, 2022.
Article in English | MEDLINE | ID: mdl-35830291

ABSTRACT

OBJECTIVE: To explore the optimal cut-off value of serum procalcitonin (PCT) level in predicting bacterial infection in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: 204 hospitalized patients with AECOPD were enrolled in this study. Their diagnoses and treatments followed routine protocols in Fu-Xing Hospital affiliated to Capital Medical University, Beijing, China. Extra blood samples were taken for serum PCT level testing and the results were blinded to the treating physicians. On discharge, clinical data were collected and the treating physicians made comprehensive analyses to determine whether the AECOPD were triggered by respiratory tract bacterial infection or non-bacterial causes according to the "new diagnostic criteria" defined in this study. In the AECOPD patients with bacterial infection, treating physicians decided whether they had bacterial pneumonia based on imaging studies. Receiver operating characteristic curve (ROC) was used to analyze the accuracy of serum PCT level in predicting bacterial infection. RESULTS: In the 173 AECOPD patients who did not have pneumonia, 115 had evidences of bacterial infection while 58 did not. The median PCT levels were 0.1(0.08, 0.18) ng/ml and 0.07 (0.05, 0.08) ng/ml for each group, which were statistically different. The proposed optimal cut-off value of serum PCT level in predicting bacterial infection was 0.08 ng/mL according to this study, with a sensitivity of 81%, specificity of 67% and area under the ROC curve (AUC) of 0.794. There were 31 AECOPD patients diagnosed with pneumonia, their median PCT level was 0.23 ng/mL. CONCLUSIONS: The serum PCT levels slightly increased in the majority of hospitalized patients with AECOPD compared with reference range. When PCT level was ≥0.08 ng/mL, AECOPD was more likely to be caused by bacterial infection. A significantly elevated PCT levels may indicate combination of AECOPD and bacterial pneumonia.


Subject(s)
Pneumonia, Bacterial , Procalcitonin , Pulmonary Disease, Chronic Obstructive , Biomarkers/blood , C-Reactive Protein/metabolism , Humans , Pneumonia, Bacterial/blood , Pneumonia, Bacterial/diagnosis , Procalcitonin/blood , Pulmonary Disease, Chronic Obstructive/blood , Pulmonary Disease, Chronic Obstructive/diagnosis , ROC Curve
5.
Crit Care Med ; 45(7): 1160-1167, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28422775

ABSTRACT

OBJECTIVE: To evaluate the contemporary practice, outcomes, and costs related to mechanical ventilation among ICUs in China. DESIGN: A prospective observational cohort study. SETTING: Fourteen ICUs among 13 hospitals in Beijing, China. PATIENTS: Seven hundred ninety-three patients who received at least 24 hours of mechanical ventilation within the first 48 hours of ICU stay. INTERVENTION: None. MEASUREMENTS AND RESULTS: The mean age was 64 years. Sixty-three percent were male. New acute respiratory failure accounted for 85.5% of mechanical ventilation cases. Only 4.7% of the patients received mechanical ventilation for acute exacerbation of chronic obstructive pulmonary disease. The most widely used ventilation mode was the combination of synchronized intermittent mandatory ventilation and pressure support (43.6%). Use of lung-protective ventilation is widespread with tidal volumes of 7.1 mL/kg (2.1 mL/kg). The ICU/hospital mortality was 27.6%/29.3%, respectively (8.5%/9.7% for surgical patients and 41.3%/43.2% for medical patients, respectively). The mean level of ICU/hospital cost per patient was $15,271 (18,940)/$22,946 (25,575), respectively. The mean daily ICU cost per patient was $1,212. CONCLUSION: For the first time, we obtained a preliminary epidemiology data of mechanical ventilation in Beijing, China, through the study. Compared with the other nations, our patients are older, predominantly male, and treated according to prevailing international guidelines yet at a relatively high cost and high mortality. The expanding elderly population predicts increase demand for mechanical ventilation that must be met by continuous improvement in quality and efficiency of critical care services.


Subject(s)
Intensive Care Units/economics , Respiration, Artificial/economics , Respiration, Artificial/methods , Adolescent , Adult , Aged , Aged, 80 and over , Beijing , Blood Gas Analysis , Female , Hospital Costs/statistics & numerical data , Hospital Mortality , Humans , Male , Middle Aged , Prospective Studies , Respiratory Distress Syndrome/therapy , Retrospective Studies , Tidal Volume , Young Adult
6.
Ying Yong Sheng Tai Xue Bao ; 26(4): 1231-6, 2015 Apr.
Article in Chinese | MEDLINE | ID: mdl-26259468

ABSTRACT

Abstract: Fusarium wilt is a soil borne disease caused by plant continuous cropping in monoculture Chrysanthemum morifolium 'Youxiang' monoculture not only declines plant quality and yield but also decreases soil enzymes and soil microbial diversity over successive cultivation. In this article, the effects of fungicide (Carbendazim MBC), antifungal enhanced bio-organic fertilizer (BOF), and their combined application on the quality and soil enzymes activities of Chrysanthemum morifolium 'Youxiang' in continuous cropping systems were investigated. The results showed that both bioorganic fertilizer (BOF) and fungicide (MBC) single application could effectively prevent the occurrence of Fusarium wilt disease of cut chrysanthemum. Bio-organic fertilizer application was more effective on root activity, soil enzymes activities and quality (shoot height, stem diameter, leaf SPAD value, ray floret number, shoot fresh mass) improvement of cut chrysanthemum, while fungicide single application was responsible for soil enzymatic activities suppression to some extent. The combined application treatment (MBC+BOF) showed the best effects on quality improvement and soil enzyme activities promotion.


Subject(s)
Agriculture/methods , Chrysanthemum/growth & development , Fertilizers , Fungicides, Industrial , Soil Microbiology , Soil/chemistry , Chrysanthemum/microbiology , Enzymes/chemistry , Fusarium , Plant Leaves , Plant Roots , Plant Stems
7.
FEBS Lett ; 588(9): 1659-65, 2014 May 02.
Article in English | MEDLINE | ID: mdl-24631538

ABSTRACT

Exposure to ethanol levels reached in circulation during alcohol intoxication (>10mM) constricts cerebral arteries in rats and humans. Remarkably, targets and mechanisms underlying this action remain largely unidentified. Artery diameter is regulated by myocyte Ca(2+) sparks, a vasodilatory signal contributed to by type 2 ryanodine receptors (RyR2). Using laser confocal microscopy in rat cerebral arteries and bilayer electrophysiology we unveil that ethanol inhibits both Ca(2+) spark and RyR2 activity with IC50<20 mM, placing RyR2 among the ion channels that are most sensitive to ethanol. Alcohol directly targets RyR2 and its lipid microenvironment, leading to stabilization of RyR2 closed states.


Subject(s)
Calcium Channel Blockers/pharmacology , Calcium Signaling/drug effects , Ethanol/pharmacology , Ryanodine Receptor Calcium Release Channel/metabolism , Alcoholic Intoxication/physiopathology , Animals , Central Nervous System Depressants/pharmacology , Cerebral Arteries/drug effects , Cerebral Arteries/physiopathology , HEK293 Cells , Humans , In Vitro Techniques , Inhibitory Concentration 50 , Ion Channel Gating/drug effects , Male , Protein Stability , Rats , Rats, Sprague-Dawley
8.
Zhonghua Nei Ke Za Zhi ; 51(8): 626-9, 2012 Aug.
Article in Chinese | MEDLINE | ID: mdl-23158862

ABSTRACT

OBJECTIVE: To assess the diagnostic predictive value of Wells score and modified Geneva score for acute pulmonary embolism by prospective case series and to explore a more suitable scoring system for Chinese population. METHODS: All the patients suspected of pulmonary embolism (PE) and received CT pulmonary angiography (CTPA) were enrolled consecutively in Fuxing Hospital, Capital Medical University, China, from June 2009 to August 2011. Before CTPA test or on condition that test results were unknown, clinical scoring was assessed prospectively by the Wells score and the modified Geneva score. The probability of PE in each patient was assessed and the patients were divided into low, moderate and high probability groups according to the clinical scores. The result of CTPA was used as the diagnostic gold standard for PE. Diagnostic accuracy in each group was analyzed. The predictive accuracy of both scores was compared by AUC(ROC) curve. RESULTS: A total of 139 patients met our enrollment criteria and 117 eligible patients entered our study at last. PE was diagnosed in 47 patients by CTPA with an overall prevalence of 40.2%.Prevalence of PE in the low, moderate and high pretest probability groups assessed by the Wells score and by the simplified modified Geneva score were 7.1% (3/42), 42.9% (21/49), 88.5% (23/26) and 10.0% (3/30), 48.1% (37/77), 7/10, respectively. AUC(ROC) curves for the Wells score and the simplified modified Geneva score were 0.872 (95%CI 0.810 - 0.933) and 0.734 (95%CI 0.643 - 0.825) respectively, with a significant difference (P = 0.005). CONCLUSION: The Wells score is more accurate for clinical predicting acute PE than the modified Geneva score.


Subject(s)
Pulmonary Embolism/diagnosis , Adult , Aged , Aged, 80 and over , Angiography , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Pulmonary Embolism/diagnostic imaging , ROC Curve , Young Adult
9.
Heart Rhythm ; 9(6): 953-60, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22245792

ABSTRACT

BACKGROUND: Ranolazine (Ran) is known to inhibit multiple targets, including the late Na(+)current, the rapid delayed rectifying K(+)current, the L-type Ca(2+)current, and fatty acid metabolism. Functionally, Ran suppresses early afterdepolarization (EADs) and torsades de pointes (TdP) in drug-induced long QT type 2 (LQT2) presumably by decreasing intracellular [Na(+)](i) and Ca(2+)overload. However, simulations of EADs in LQT2 failed to predict their suppression by Ran. OBJECTIVE: To elucidate the mechanism(s) whereby Ran alters cardiac action potentials (APs) and cytosolic Ca(2+)transients and suppresses EADs and TdP in LQT2. METHODS: The known effects of Ran were included in simulations (Shannon and Mahajan models) of rabbit ventricular APs and Ca(2+)transients in control and LQT2 models and compared with experimental optical mapping data from Langendorff rabbit hearts treated with E4031 (0.5 µM) to block the rapid delayed rectifying K(+)current. Direct effects of Ran on cardiac ryanodine receptors (RyR2) were investigated in single channels and changes in Ca(2+)-dependent high-affinity ryanodine binding. RESULTS: Ran (10 µM) alone prolonged action potential durations (206 ± 4.6 to 240 ± 7.8 ms; P <0.05); E4031 prolonged action potential durations (204 ± 6 to 546 ± 35 ms; P <0.05) and elicited EADs and TdP that were suppressed by Ran (10 µM; n = 7 of 7 hearts). Simulations (Shannon but not Mahajan model) closely reproduced experimental data except for EAD suppression by Ran. Ran reduced open probability (P(o)) of RyR2 (half maximal inhibitory concentration = 10 ± 3 µM; n = 7) in bilayers and shifted half maximal effective concentration for Ca(2+)-dependent ryanodine binding from 0.42 ± 0.02 to 0.64 ± 0.02 µM with 30 µM Ran. CONCLUSIONS: Ran reduces P(o) of RyR2, desensitizes Ca(2+)-dependent RyR2 activation, and inhibits Ca(i) oscillations, which represents a novel mechanism for its suppression of EADs and TdP.


Subject(s)
Acetanilides/pharmacology , Long QT Syndrome/complications , Myocardium/metabolism , Piperazines/pharmacology , Ryanodine Receptor Calcium Release Channel/metabolism , Torsades de Pointes/drug therapy , Action Potentials/drug effects , Animals , Disease Models, Animal , Electrophysiologic Techniques, Cardiac/methods , Enzyme Inhibitors/pharmacology , Female , Follow-Up Studies , Long QT Syndrome/drug therapy , Long QT Syndrome/physiopathology , Rabbits , Ranolazine , Ryanodine Receptor Calcium Release Channel/drug effects , Torsades de Pointes/etiology , Torsades de Pointes/physiopathology , Treatment Outcome
10.
Mol Pharmacol ; 81(1): 53-62, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21989257

ABSTRACT

New drugs with enhanced electron donor properties that target the ryanodine receptor from skeletal muscle sarcoplasmic reticulum (RyR1) are shown to be potent inhibitors of single-channel activity. In this article, we synthesize derivatives of the channel activator 4-chloro-3-methyl phenol (4-CmC) and the 1,4-benzothiazepine channel inhibitor 4-[-3{1-(4-benzyl) piperidinyl}propionyl]-7-methoxy-2,3,4,5-tetrahydro-1,4-benzothiazepine (K201, JTV519) with enhanced electron donor properties. Instead of activating channel activity (~100 µM), the 4-methoxy analog of 4-CmC [4-methoxy-3-methyl phenol (4-MmC)] inhibits channel activity at submicromolar concentrations (IC(50) = 0.34 ± 0.08 µM). Increasing the electron donor characteristics of K201 by synthesizing its dioxole congener results in an approximately 16 times more potent RyR1 inhibitor (IC(50) = 0.24 ± 0.05 µM) compared with K201 (IC(50) = 3.98 ± 0.79 µM). Inhibition is not caused by an increased closed time of the channel but seems to be caused by an open state block of RyR1. These alterations to chemical structure do not influence the ability of these drugs to affect Ca(2+)-dependent ATPase activity of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase type 1. Moreover, the FKBP12 protein, which stabilizes RyR1 in a closed configuration, is shown to be a strong electron donor. It seems as if FKBP12, K201, its dioxole derivative, and 4-MmC inhibit RyR1 channel activity by virtue of their electron donor characteristics. These results embody strong evidence that designing new drugs to target RyR1 with enhanced electron donor characteristics results in more potent channel inhibitors. This is a novel approach to the design of new, more potent drugs with the aim of functionally modifying RyR1 single-channel activity.


Subject(s)
Calcium Channel Blockers/chemical synthesis , Calcium Channel Blockers/metabolism , Drug Discovery , Ryanodine Receptor Calcium Release Channel/metabolism , Thiazepines/chemistry , Thiazepines/metabolism , Animals , Calcium Channel Blockers/pharmacology , Calcium Channels/chemical synthesis , Calcium Channels/metabolism , Calcium Signaling/drug effects , Calcium Signaling/physiology , Drug Discovery/methods , Electron Transport/physiology , Muscle, Skeletal/cytology , Muscle, Skeletal/metabolism , Muscle, Skeletal/physiology , Protein Stability/drug effects , Rabbits , Ryanodine Receptor Calcium Release Channel/chemical synthesis
11.
Clin Geriatr Med ; 27(2): 259-71, 2011 May.
Article in English | MEDLINE | ID: mdl-21641510

ABSTRACT

This article reviews the literature on transitional care to and from the LTC environment, highlighting strategies to improve the quality of care transitions. Several factors are vital in the improvement of systems of care dealing with transitions. Key factors include communication with and among health care providers, effective medication reconciliation, advanced discharge planning, and timely use of palliative care.


Subject(s)
Continuity of Patient Care/organization & administration , Long-Term Care , Patient Transfer/organization & administration , Quality Assurance, Health Care , Aged , Aged, 80 and over , Communication , Hospitalization , Humans , Medication Reconciliation , Patient Discharge
13.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 19(9): 536-8, 2007 Sep.
Article in Chinese | MEDLINE | ID: mdl-17767822

ABSTRACT

OBJECTIVE: To investigate the patterns of pulmonary function in severe acute respiratory syndrome (SARS) patients during three-year convalescent period, and to investigate the changes and the medium and long term effects on pulmonary function of SARS patients. METHODS: Pulmonary function tests were conducted for four times in 37 SARS patients during three-year convalescent period. They were discharged from hospital within one month, three months, one year and three years respectively. At the same time, pulmonary function of 15 healthy persons was examined as controls to be used for comparison. RESULTS: Compared with the healthy controls, there were significant decrease in forced vital capacity (FVC), vital capacity (VC), one second forced expiratory volume (FEV1), 25%-75% forced expiratory flow (25%-75%FEF) of SARS patients within three years after their discharge from hospital (all P<0.05). There were no significant differences in FEV1/FVC, total lung capacity (TLC), diffusing capacity of the lung for carbon monoxide (DLCO) between the two groups (all P>0.05). Abnormality rate of DLCO in the SARS patients within three years after discharge was significantly decreased (32.4% vs. 5.4%,P<0.05), but no significant differences in FVC, VC, 25%-75%FEF among SARS patients discharged one month and three years from the hospital (all P>0.05). Ten SARS patients showed lower FVC (mild degree in 9 cases, severe degree in 1 case) three years later, 2 patients showed mildly lowered DLCO. CONCLUSION: The lung diffusion function of the SARS patients had recovered after they were discharged from hospital within three years, but in 20%-30% patients there is still mild or moderate restrictive ventilation function abnormality and small airway function impairment. The lung functions of most patients have recovered gradually, but in a minority of patients they may be impaired.


Subject(s)
Lung/physiopathology , Severe Acute Respiratory Syndrome/physiopathology , Adolescent , Adult , Aged , Female , Follow-Up Studies , Forced Expiratory Volume , Humans , Male , Middle Aged , Pulmonary Diffusing Capacity , Severe Acute Respiratory Syndrome/rehabilitation , Total Lung Capacity , Vital Capacity , Young Adult
14.
Neth Heart J ; 13(10): 370-371, 2005 Oct.
Article in English | MEDLINE | ID: mdl-25696422
15.
J Med Chem ; 47(24): 5821-4, 2004 Nov 18.
Article in English | MEDLINE | ID: mdl-15537337

ABSTRACT

Some piperidine-based nocaine/modafinil hybrid ligands have been designed, synthesized, and found to display an improved potency at all three monoamine transporters and particularly for DAT and/or NET. Some highly active and selective monoamine transporter inhibitors with low nanomolar to subnanomolar potency were identified. Ligands of this type may find important applications as positron emission tomography imaging tools and in the treatment of central nervous system disorders such as depression and sleep apnea.


Subject(s)
Benzhydryl Compounds/chemical synthesis , Membrane Glycoproteins/antagonists & inhibitors , Membrane Transport Modulators , Membrane Transport Proteins/antagonists & inhibitors , Nerve Tissue Proteins/antagonists & inhibitors , Piperidines/chemical synthesis , Symporters/antagonists & inhibitors , Animals , Benzhydryl Compounds/chemistry , Benzhydryl Compounds/pharmacology , Biological Availability , Cocaine/pharmacology , Dopamine Plasma Membrane Transport Proteins , Drug Design , In Vitro Techniques , Ligands , Modafinil , Motor Activity/drug effects , Nerve Endings/drug effects , Nerve Endings/metabolism , Norepinephrine Plasma Membrane Transport Proteins , Piperidines/chemistry , Piperidines/pharmacology , Rats , Serotonin Plasma Membrane Transport Proteins , Synaptosomes/drug effects , Synaptosomes/metabolism
16.
Bioorg Med Chem Lett ; 13(20): 3565-9, 2003 Oct 20.
Article in English | MEDLINE | ID: mdl-14505672

ABSTRACT

To further explore the structure-activity relationships (SARs) of certain tropanes, and to gain insights into the structural features required for high activity and selectivity at norepinephrine transporters (NET), we have introduced both five- and six-membered heteroaromatic moieties such as substituted pyridyl, pyrazinyl, pyrimidyl, thiazolyl, and mono- or disubstituted thienyl groups into conformationally constrained, tricyclic tropane analogues. A number of (Z)-9-(heteroarylmethylene)-7-azatricyclo[4.3.1.0(3,7)]decanes were synthesized, and their abilities to block dopamine, serotonin, and norepinephrine reuptake by their respective transporters were evaluated. It was found that the five- or six-membered N-containing aromatics are too basic to display high NET activity, while some of the thiophene analogues were identified as potent and selective NET inhibitors.


Subject(s)
Symporters/antagonists & inhibitors , Thiophenes/chemical synthesis , Norepinephrine Plasma Membrane Transport Proteins , Thiophenes/chemistry , Thiophenes/pharmacology
17.
J Pharmacol Exp Ther ; 304(1): 266-71, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12490600

ABSTRACT

Repetitive administration of phencyclidine (PCP) in the perinatal period results in cortical apoptosis and a long-lasting deficit in sensorimotor gating. Because these changes are olanzapine-sensitive, we have suggested that the effects of perinatal PCP could be used to model certain aspects of schizophrenia. Studies of PCP and N-methyl-D-aspartate-induced cell death suggested that superoxide could play a role in the pathway leading to death after PCP administration. The purpose of the current study was to determine whether the in vivo administration of M40403, a superoxide dismutase mimetic, could prevent PCP-induced cortical apoptosis and/or deficits in prepulse inhibition. Perinatal rat pups were administered 10 mg/kg PCP on postnatal (PN) days 7, 9, and 11 with or without treatment with 10 mg/kg M40403. Pups were either killed on PN 12 for analysis of various apoptotic markers or they were assessed for prepulse inhibition on PN 24 to 26. Treatment with M40403 2 and 24 h after each PCP treatment prevented PCP-induced increases in two measures of apoptosis in the dorsolateral frontal cortex and in the olfactory cortex. PCP-induced proapoptotic changes in Bax and Bcl-X(L) were also prevented by M40403 treatment. This regimen did not prevent the deficit in prepulse inhibition caused by PCP treatment, but when the treatment regimen was extended through PN 23, M40403 completely prevented the PCP-induced deficit in prepulse inhibition. These data suggest that perinatal PCP treatment leads to long-lasting changes in the pathway(s), leading to cell death and behavioral deficits, and that the superoxide radical plays a critical role in the underlying mechanism.


Subject(s)
Apoptosis/drug effects , Cerebral Cortex/cytology , Excitatory Amino Acid Antagonists/pharmacology , Free Radical Scavengers/pharmacology , Organometallic Compounds/pharmacology , Phencyclidine/antagonists & inhibitors , Phencyclidine/pharmacology , Reflex, Startle/drug effects , Superoxide Dismutase/pharmacology , Acoustic Stimulation , Animals , Blotting, Western , Cerebral Cortex/drug effects , DNA Fragmentation/drug effects , Female , In Situ Nick-End Labeling , Manganese , Molecular Mimicry , Neurotoxicity Syndromes/pathology , Neurotoxicity Syndromes/psychology , Pregnancy , Rats , Rats, Sprague-Dawley
18.
J Pharmacol Exp Ther ; 301(2): 478-87, 2002 May.
Article in English | MEDLINE | ID: mdl-11961046

ABSTRACT

N-Methyl-D-aspartate (NMDA) receptor-mediated cell death is complex, probably involving elements of necrosis and apoptosis. The mechanisms underlying this phenomenon are incompletely understood but have been suggested to involve reactive oxygen species such as nitric oxide and superoxide anion (O(2)) and nuclear factor-kappaB (NF-kappaB) signaling. In this study, we used a selective nonpeptidyl superoxide dismutase mimetic (M40403) and SN50, a peptide inhibitor of NF-kappaB translocation, to investigate the role of O(2) and the potential downstream signaling molecules in cell death induced by activation of the NMDA receptor. Application of NMDA to a mixed neuronal/glial forebrain culture resulted in an early increase in the release of cytoplasmic lactate dehydrogenase (LDH), which peaked at 4 h. This was followed by a reduction in mitochondrial metabolism of the dye MTT [3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] that continued to decrease throughout the 20-h exposure. A substantial increase in DNA fragmentation as measured by an enzyme-linked immunosorbent assay (ELISA) specific for DNA-associated histone proteins (nucleosomes) was observed at 7 and 20 h. M40403 and SN50 blocked NMDA-induced changes in LDH release at 2, 4, and 20 h, MTT metabolism at 4 and 20 h, and DNA fragmentation at 20 h as measured by the ELISA and by an increase in terminal dUTP-nick end labeling. M40403 also prevented NMDA-induced nuclear transport of NF-kappaB and increased expression of Bax relative to Bcl-X(L). SN50 was also able to block NMDA-induced cell death as well as the increased Bax/Bcl-X(L) ratio. Time course studies and experiments with SN50 and M40403 suggest that O(2) production and NF-kappaB translocation may be involved in necrosis and apoptosis, but the latter also requires an increased expression of Bax. The ability of M40403 to prevent NMDA-induced cell death relatively early in this cascade suggests its potential therapeutic utility in central nervous systems diseases such as stroke that are associated with increased NMDA receptor-mediated production of O(2).


Subject(s)
Apoptosis/physiology , Excitatory Amino Acid Agonists/pharmacology , N-Methylaspartate/pharmacology , NF-kappa B/physiology , Superoxides/metabolism , Animals , Cells, Cultured , Electrophoretic Mobility Shift Assay , Necrosis , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction , bcl-2-Associated X Protein , bcl-X Protein
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