Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxidative stress plays an important role in the pathogenesis of neurodegenerative diseases, such as Parkinson's disease (PD). There are several methods to measure oxidative stress, being lipid peroxidation (LPO) one of the most frequently used. Endogenous plasma LPO was determined by a spectrofluorimetric method in fifty two patients with sporadic PD and in forty controls. To know the maximum capacity of lipids to peroxidate, LPO was also measured after co-incubation with Fe2+/H2O2 (exogenous LPO). All PD patients were taken L-dopa and the effect of this treatment on LPO levels was additionally studied. Urine catecholamines and their main metabolites were also analyzed, and their possible correlation to LPO statistically studied. Endogenous plasma LPO levels were 33% higher in PD group than in control group (P<0.001). Exogenous plasma or oxidizability was also higher in PD patients compared to controls (20%, P<0.05). The intake of L-dopa was negatively dose-related to endogenous and exogenous plasma LPO. In conclusion, plasma of PD patients has elevated levels of LPO and also is more prone to peroxidation than that in the control group. The results also suggest an antioxidant effect of L-dopa.
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PMID:Plasma lipid peroxidation in sporadic Parkinson's disease. Role of the L-dopa. 1621 27

Chronic infusion of rotenone (Rot) to Lewis rats reproduces many features of Parkinson disease. Rot (3 mg/kg/day) was infused subcutaneously to male Lewis rats for 6 days using Alzet minipumps. Control rats received the vehicle only. Presence of 0.1% bovine serum albumin during the isolation procedure completely removed rotenone bound to the mitochondria. Therefore all functional changes observed were aftereffects of rotenone toxicity in vivo. In Rot rat brain mitochondria (Rot-RBM) there was a 30-40% inhibition of respiration in State 3 and State 3U with Complex I (Co-I) substrates and succinate. Rot did not affect the State 4Deltapsi of RBM and rat liver mitochondria (RLM). However, Rot-RBM required two times less Ca2+ to initiate permeability transition (mPT). There was a 2-fold increase in O*2- or H2O2 generation in Rot-RBM oxidizing glutamate. Rot infusion affected RLM little. Our results show that in RBM, the major site of reactive oxygen species generation with glutamate or succinate is Co-I. We also found that Co-II generates substantial amounts of reactive oxygen species that increased 2-fold in the Rot-RBM. Our data suggest that the primary mechanism of the Rot toxic effect on RBM consists in a significant increase of O*2- generation that causes damage to Co-I and Co-II, presumably at the level of 4Fe-4S clusters. Decreased respiratory activity diminishes resistance of RBM to Ca2+ and thus increases probability of mPT and apoptotic cell death. We suggest that the damage to Co-I and Co-II shifts O*2- generation from the CoQ10 sites to more proximal sites, such as flavines, and makes it independent of the RBM functional state.
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PMID:Rotenone model of Parkinson disease: multiple brain mitochondria dysfunctions after short term systemic rotenone intoxication. 1624 45

Mitochondrial dysfunction is a potential causal factor in Parkinson's disease. We show here that acute exposure to the mitochondrial complex I inhibitor rotenone (30-100 nM; 30 min) causes concentration-dependent suppression of single-pulse evoked dopamine (DA) release monitored in real time with carbon-fiber microelectrodes in guinea pig striatal slices, with no effect on DA content. Suppression of DA release was prevented by the sulfonylurea glibenclamide, implicating ATP-sensitive K+ (KATP) channels; however, tissue ATP was unaltered. Because KATP channels can be activated by hydrogen peroxide (H2O2), as well as by low ATP, we examined the involvement of rotenone-enhanced H2O2 generation. Confirming an essential role for H2O2, the inhibition of DA release by rotenone was prevented by catalase, a peroxide-scavenging enzyme. Striatal H2O2 generation during rotenone exposure was examined in individual medium spiny neurons using fluorescence imaging with dichlorofluorescein (DCF). An increase in intracellular H2O2 levels followed a similar time course to that of DA release suppression and was accompanied by cell membrane depolarization, decreased input resistance, and increased excitability. Extracellular catalase markedly attenuated the increase in DCF fluorescence and prevented rotenone-induced effects on membrane properties; membrane changes were also largely prevented by flufenamic acid, a blocker of transient receptor potential (TRP) channels. Thus, partial mitochondrial inhibition can cause functional DA denervation via H2O2 and KATP channels, without DA or ATP depletion. Furthermore, amplified H2O2 levels and TRP channel activation in striatal spiny neurons indicate potential sources of damage in these cells. Overall, these novel factors could contribute to parkinsonian motor deficits and neuronal degeneration caused by mitochondrial dysfunction.
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PMID:Partial mitochondrial inhibition causes striatal dopamine release suppression and medium spiny neuron depolarization via H2O2 elevation, not ATP depletion. 1625 52

Heme oxygenase-1 (HO-1) has been strongly highlighted because of its induction in many cell types by toxic stimuli, including oxidative stress. The intense HO-1 immunostaining in the substantia nigra of Parkinson disease (PD) patients suggests its involvement in the pathogenesis of this neurodegenerative disease. In this work we investigated HO-1 expression in rat substantia nigra postnatal cell cultures under conditions mimicking dopamine toxicity and its modulation by glial cell line-derived neurotrophic factor (GDNF), a potent neuroprotective factor for dopaminergic neurons. In neuron-glia cultures, we found that H2O2, a product of dopamine metabolism, or l-3,4-dihydroxyphenylalanine (L-DOPA), the dopamine precursor used in the therapy of PD, induced a fast up-regulation of HO-1 mRNA and protein levels, followed by a secondary down-regulation. H2O2 and L-DOPA also increased HO-1 expression in astrocyte cultures, but with a delayed time course in H2O2-treated cultures. HO-1 expression was decreased in neuron-glia cultures under conditions under which GDNF up-regulation was observed. Because exogenously applied GDNF prevented HO-1 up-regulation in cultures treated with H2O2 or l-DOPA, and antibody neutralization of GDNF prevented the secondary HO-1 down-regulation observed in neuron-glia cultures, we propose that GDNF negatively modulates HO-1 expression induced by oxidative stress. To our knowledge, this is the first report showing the modulation of HO-1 expression by GDNF.
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PMID:GDNF modulates HO-1 expression in substantia nigra postnatal cell cultures. 1629 86

DJ-1 is a novel oncogene and causative gene for familial form of the Parkinson's disease (PD). DJ-1 has been shown to play a role in anti-oxidative stress by eliminating reactive oxygen species (ROS). The onset of PD is thought to be caused by oxidative stress and mitochondrial injury, which leads to protein aggregation that results in neuronal cell death. However, the mechanism by which DJ-1 triggers the onset of PD is still not clear. In this study, we analyzed association and localization of DJ-1 and its mutants with various chaperones. The results showed that DJ-1 and its mutants were associated with Hsp70, CHIP and mtHsp70/Grp75, a mitochondria-resident Hsp70, and that L166P and M26I mutants found in PD patients were strongly associated with Hsp70 and CHIP compared to wild-type and other DJ-1 mutants. DJ-1 and its mutants were colocalized with Hsp70 and CHIP in cells. Furthermore, association and colocalization of wildtype DJ-1 with mtHsp70 in mitochondria were found to be enhanced by treatment of cells with H2O2. These results suggest that translocation of DJ-1 to mitochondria after oxidative stress is carried out in association with chaperones.
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PMID:Association of DJ-1 with chaperones and enhanced association and colocalization with mitochondrial Hsp70 by oxidative stress. 1629 34

Pramipexole, a novel non-ergot dopamine (DA) agonist, has been successfully applied to the treatment of Parkinson's disease (PD). Although the specific cause of PD remains unknown, recent studies have provided evidence that oxidative stress plays a role in the parthenogenesis of the disease. In the present study, we examined the effect of pramipexole on hydrogen peroxide (H2O2, 100 microM)-induced PC12 cell death, and the intracellular mechanism of this effect. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay revealed that pretreatment of PC12 cells with pramipexole (1-100 microM) resulted in significant protection against H2O2-induced cell death in a concentration-dependent manner. The protective effect of pramipexole was not affected by pretreatment with the DA receptor antagonists sulpiride, spiperone or domperidone, suggesting that the effect of pramipexole is not mediated by DA receptors. In PC12 cells, pramipexole inhibited H2O2-induced lactate dehydrogenase (LDH) leakage, as well as H2O2-induced cytochrome c release and caspase-3 activation with the resultant apoptosis. It was also observed in PC12 cells that H2O2 stimulated phosphorylation of mitogen-activated protein (MAP) kinases, i.e., extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase. Pramipexole inhibited H2O2-induced JNK and p38 MAP kinase, but not ERK1/2 phosphorylation. Furthermore, in these cells experiments with a fluorescent probe, 2-[6-(4'-amino)phenoxy-3H-xanthen-3-on-9-yl]benzoic acid, revealed that pramipexole, the JNK inhibitor SP600125 and the p38 MAP kinase inhibitor SB203580 inhibited the generation of H2O2-induced reactive oxygen species. Caspase inhibitors Z-DEVD-FMK and Z-IETD-FMK, as well as SP600125 and SB203580, inhibited H2O2-induced PC12 cell death to a similar extent as pramipexole. These results suggest that pramipexole exerts a protective effect against oxidative stress-induced PC12 cell death in part through an inhibition of JNK and p38 MAP kinase.
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PMID:Pramipexole protects against H2O2-induced PC12 cell death. 1636 28

Oxidative stress caused by various stimuli lead to oxidation of glutathione (GSH), the major redox power of the cell. Amyloid beta [Abeta(1-42)] is one of the key components of senile plaques and is involved in the progress initiation and triggers of Alzheimer's disease (AD). Lower GSH levels correlated with the activation of mitogen-activated proteins kinases (MAPK) have been demonstrated in AD, Parkinson's disease (PD) and other neurodegenerative disorders and have been proposed to play a central role in the deterioration of the aging and neurodegenerative brain. In this study, we evaluated the ability of low molecular weight thiol amides, N-acetyl cysteine amide (AD4) that replenishes GSH levels, N-acetyl glycine cysteine amide (AD7) and N-acetyl-Cys-Gly-Pro-Cys-amide (CB4) to protect primary neuronal culture against the oxidative and neurotoxic effects of Abeta(1-42) and to inhibit cisplatin- and hydrogen-peroxide-induced phosphorylation of two MAP kinases (MAPK), p38 and ERK1/2, in NIH3T3 cells. Cell death induced by Abeta(1-42) in primary neuronal cells was reversed by the thiol amides. Likewise, protein oxidation, loss of mitochondrial function and DNA fragmentation all returned to control levels by pretreatment with the three thiol amides. Elevated phosphorylation of ERK1/2 and p38 induced by cisplatin or H2O2 in NIH3T3 cells was lowered by AD4, AD7 and CB4 in a dose-dependent manner. Taken together, these results suggest that the thiol amides AD4, AD7 and CB4 protect neuronal cells against Abeta(1-42) toxicity by attenuating oxidative stress in correlation with inhibiting the MAPK phosphorylation cascade. These results are consistent with the notion that these small molecular thiol amides may play a viable protective role in the oxidative and neurotoxicity induced by Abeta(1-42) in AD brain.
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PMID:Low molecular weight thiol amides attenuate MAPK activity and protect primary neurons from Abeta(1-42) toxicity. 1638 19

DJ-1 is a novel oncogene and causative gene for the familial form of Parkinson's disease (PD). DJ-1 has multiple functions, including anti-oxidative stress by eliminating reactive oxygen species (ROS) and transcriptional regulation as a coactivator, and loss of these functions are thought to trigger the onset of PD. The mechanism underlying the prevention of cell death by DJ-1 is, however, not clear. In this study, we found that DJ-1 directly bound to homeodomaininteracting protein kinase 1 (HIPK1) in vitro and in vivo and that these proteins were colocalized in the nucleus. HIPK1 was then found to be degraded in human H1299 cells transfected with wild-type DJ-1 but not with a C106S DJ-1 mutant, a DJ-1 protein disrupting a catalytic domain of the putative protease, in a dose-dependent manner. Furthermore, although knockdown of either DJ-1 or HIPK1 rendered H1299 cells susceptible to H2O2-induced cell death, double-knockdown of DJ-1 and HIPK1 rendered H1299 cells resistant to H2O2-induced cell death, suggesting that the elevated level of HIPK1 induced by a low level of DJ-1 inhibits oxidative stress-induced cell death.
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PMID:DJ-1 interacts with HIPK1 and affects H2O2-induced cell death. 1639 Aug 25

Reactive oxygen species (ROS) are important mediators in a number of neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The neuroprotective effects of flavonoids from the stems and leaves of Scutellaria baicalensis Georgi (SSF) against hydrogen peroxide (H2O2)-induced rat pheochromocytoma line PC12 injury were evaluated by cell lesion, free radicals and ATPase disorders. Following a 30 min exposure of the cells to H2O2 (100 microm), a marked decrease in cell survival and activity of superoxide dismutase (SOD) and Na+-K+-ATPase as well as an increase of malondialdehyde (MDA) production and lactate dehydrogenase (LDH) release were observed. Pretreatment of the cells with SSF (18-76 microg/mL) prior to H2O2 exposure notably elevated the cell survival and activity of SOD and Na+-K+-ATPase, and lowered the MDA level and LDH release. Neuroprotection by SSF was also observed in animal models. The present results indicated that SSF exerts neuroprotective effects against H2O2 toxicity, which might be of importance and might contribute to its clinical efficacy for the treatment of neurodegenerative disease.
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PMID:Prevention of oxidative injury by flavonoids from stems and leaves of Scutellaria baicalensis Georgi in PC12 cells. 1639 22

A series of multifunctional codrugs (1-4), obtained by joining L-Dopa (LD) and dopamine (DA) with (R)-alpha-lipoic acid (LA), was synthesized and evaluated as potential codrugs with antioxidant and iron-chelating properties. These multifunctional molecules were synthesized to overcome the pro-oxidant effect associated with LD therapy. The physicochemical properties, together with the chemical and enzymatic stabilities of synthesized compounds, were evaluated in order to determine both their stability in aqueous medium and their sensitivity in undergoing enzymatic cleavage by rat and human plasma to regenerate the original drugs. The new compounds were tested for their radical scavenging activities, using a test involving the Fe (II)-H2O2-induced degradation of deoxyribose, and to evaluate peripheral markers of oxidative stress such as plasmatic activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the plasma. Furthermore, we showed the central effects of compounds 1 and 2 on spontaneous locomotor activity of rats in comparison with LD-treated animals. From the results obtained, compounds 1-4 appeared stable at a pH of 1.3 and in 7.4 buffered solution; in 80% human plasma they were turned into DA and LD. Codrugs 1-4 possess good lipophilicity (log P > 2 for all tested compounds). Compounds 1 and 2 seem to protect partially against the oxidative stress deriving from auto-oxidation and MAO-mediated metabolism of DA. This evidence, together with the "in vivo" dopaminergic activity and a sustained release of the parent drug in human plasma, allowed us to point out the potential advantages of using 1 and 2 rather than LD in treating pathologies such as Parkinson's disease, characterized by an evident decrease of DA concentration in the brain.
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PMID:L-dopa- and dopamine-(R)-alpha-lipoic acid conjugates as multifunctional codrugs with antioxidant properties. 1648 Feb 85


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