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)

Metabotropic glutamate receptors (mGluRs) share a common molecular morphology with other G protein-linked receptors, but there expression throughout the mammalian nervous system places these receptors as essential mediators not only for the initial development of an organism, but also for the vital determination of a cell's fate during many disorders in the nervous system that include amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, Huntington's disease, Multiple Sclerosis, epilepsy, trauma, and stroke. Given the ubiquitous distribution of these receptors, the mGluR system impacts upon neuronal, vascular, and glial cell function and is activated by a wide variety of stimuli that includes neurotransmitters, peptides, hormones, growth factors, ions, lipids, and light. Employing signal transduction pathways that can modulate both excitatory and inhibitory responses, the mGluR system drives a spectrum of cellular pathways that involve protein kinases, endonucleases, cellular acidity, energy metabolism, mitochondrial membrane potential, caspases, and specific mitogen-activated protein kinases. Ultimately these pathways can converge to regulate genomic DNA degradation, membrane phosphatidylserine (PS) residue exposure, and inflammatory microglial activation. As we continue to push the envelope for our understanding of this complex and critical family of metabotropic receptors, we should be able to reap enormous benefits for both clinical disease as well as our understanding of basic biology in the nervous system.
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PMID:Driving cellular plasticity and survival through the signal transduction pathways of metabotropic glutamate receptors. 1637 23

Nerve growth factor (NGF) differentiated pheochromocytoma PC12 cells exposed to 1-methyl-4-phenylpyridinium (MPP+) toxin were used as an in vitro pharmacological model of Parkinson's disease to examine the neuroprotective effects of 4-hydroxy-2,2,6,6-tetramethyl piperidine-n-oxyl (Tempol), a free radical scavenger and a superoxide dismutase-mimetic compound. MPP+-induced PC12 cell death was measured 72 h after exposure to 1.5 mM MPP+ by the release of lactate dehydrogenease, caspase-3 activation and stimulation of survival and stress mitogen-activated protein kinases. Exposure of PC12 cells to MPP+ activated ERK1 and ERK2 (forty-fold over control after 72 h), JNK1 and JNK2 (fourfold after 48 h) and p-38alpha (tenfold after 24 h). Pretreatment of PC12 cells with 500 microM Tempol, 1 h before induction of the MPP+ insult, reduced by 70% the release of LDH into the medium, inhibited caspase-3 activity by 30% and improved by 33% mitochondrial function, effects correlated with a 70% reduction in ERK1 and ERK2 phosphorylation activity. These findings support the neuroprotective effect of Tempol in the MPP+-induced PC12 cell death model and its use as a potential drug for treatment of Parkinson's disease.
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PMID:Neuroprotective effects of the stable nitroxide compound Tempol on 1-methyl-4-phenylpyridinium ion-induced neurotoxicity in the Nerve Growth Factor-differentiated model of pheochromocytoma PC12 cells. 1698 7

Neural stem cells (NSCs) possess high potencies of self-renewal and neuronal differentiation. We explored here whether transplantation of human NSCs cloned by v-myc gene transfer, HB1.F3 cells, is a feasible therapeutic option for Parkinson's disease. In vivo, green fluorescent protein-labeled HB1.F3 cells (200,000 viable cells in 3 microl of PBS) when stereotaxically transplanted (same-day lesion-transplant paradigm) into the 6-hydroxydopamine-lesioned striatum of rats significantly ameliorated parkinsonian behavioral symptoms compared with controls (vehicle, single bolus, or continuous minipump infusion of trophic factor, or killed cell grafts). Such graft-derived functional effects were accompanied by preservation of tyrosine hydroxylase (TH) immunoreactivity along the nigrostriatal pathway. Grafted HB1.F3 cells survived in the lesioned brain with some labeled with neuronal marker mitogen-activated protein 2 and decorated with synaptophysin-positive terminals. Furthermore, endogenous neurogenesis was activated in the subventricular zone of transplanted rats. To further explore the neuroprotective mechanisms underlying HB1.F3 cell transplantation, we performed cell culture studies and found that a modest number of HB1.F3 cells were TH and dopamine and cAMP-regulated phosphoprotein 32 positive, although most cells were nestin positive, suggesting a mixed population of mature and immature cells. Administration of the HB1.F3 supernatant to human derived dopaminergic SH-SY5Y cells and fetal rat ventral mesencephalic dopaminergic neurons protected against 6-hydroxydopamine neurotoxicity by suppressing apoptosis through Bcl-2 upregulation, which was blocked by anti-stem cell factor antibody alone, the phosphatidylinositol 3-kinase/Akt inhibitor LY294002 [2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one] alone, or a combination of both. These results suggest that HB1.F3 cell transplantation exerts neuroprotective effects against dopaminergic depletion in vitro and in vivo because of trophic factor secretion and neuronal differentiation.
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PMID:Transplantation of human neural stem cells exerts neuroprotection in a rat model of Parkinson's disease. 1713 12

Here we show that alpha-synuclein, a major constituent of Lewy bodies, induces inflammation in human microglial and human THP-1 cells. Secretions from such stimulated THP-1 cells contain increased levels of IL-1beta and TNF-alpha. When stimulated by alpha-synuclein in combination with IFN-gamma, secretions from the cells also become toxic towards SH-SY5Y neuroblastoma cells. The A30P, E46K and A53T alpha-synuclein mutations, which induce Parkinson's disease, are more potent than normal alpha-synuclein in the induction of such cytotoxicity. To investigate the signaling mechanisms evoked, protein phosphorylation profiling was applied. At least 81 target phospho-sites were identified. Large increases were induced in the three major mitogen-activated protein (MAP) kinase pathways: p38 MAP kinase, extracellular regulated protein-serine kinase (ERK)1/2 and c-Jun-N-terminal kinase (JNK). Upregulation occurred within minutes following exposure to alpha-synuclein, which is consistent with a receptor-mediated effect. These findings demonstrate that alpha-synuclein acts as a potent inflammatory stimulator of microglial cells, and that inhibitors of such stimulation might be beneficial in the treatment of Parkinson's disease and other synucleinopathies.
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PMID:Alpha-synuclein activates stress signaling protein kinases in THP-1 cells and microglia. 1716 28

In Parkinson's disease (PD) dopaminergic neurons in the substantia nigra (SN) become dysfunctional and many ultimately die. We report that the tellurium immunomodulating compound ammonium trichloro(dioxoethylene-O,O'-)tellurate (AS101) protects dopaminergic neurons and improves motor function in animal models of PD. It is effective when administered systemically or by direct infusion into the brain. Multifunctional activities of AS101 were identified in this study. These were mainly due to the peculiar Tellur(IV)-thiol chemistry of the compound, which enabled the compound to interact with cysteine residues on both inflammatory and apoptotic caspases, resulting in their inactivation. Conversely, its interaction with a key cysteine residue on p21(ras), led to its activation, an obligatory activity for AS101-induced neuronal differentiation. Furthermore, AS101 inhibited IL-10, resulting in up-regulation of GDNF in the SN. This was associated with activation of the neuroprotective kinases Akt and mitogen-activated protein kinases, and up-regulation of the antiapoptotic protein Bcl-2. Inhibition of caspase-1 and caspase-3 activities were associated with decreased neuronal death and inhibition of IL-1beta. We suggest that, because multiple mechanisms are involved in the dysfunction and death of neurons in PD, use of a multifunctional compound, exerting antiapoptotic, anti-inflammatory, and neurotrophic-inducing capabilities may be potentially efficacious for the treatment of PD.
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PMID:Multifunctional tellurium molecule protects and restores dopaminergic neurons in Parkinson's disease models. 1731 38

Parkinson's disease (PD) is characterized by selective loss of dopaminergic neurons in the substantia nigra of the brain. Although the underlying causes are not well characterized, epidemiological studies suggest an elevated risk of PD with occupational pesticide exposure. Here, we utilized pheochromocytoma (PC) 12 and SH-SY5Y cells as well as rat primary cultured dopaminergic neurons to investigate mechanisms for dopaminergic cell death induced by paraquat and rotenone, pesticides that are used to model PD in rodents. Both paraquat and rotenone induce selective loss of dopaminergic neurons in primary cultures. We discovered that paraquat induces apoptosis in PC12 cells but not in SH-SY5Y cells, while rotenone exposure causes apoptosis in SH-SY5Y cells but not in PC12 cells. The selective ability of paraquat and rotenone to induce apoptosis in different cell lines correlates with their ability to activate c-Jun N-terminal protein kinase (JNK) and p38 mitogen-activated protein kinases. Furthermore, JNK and p38 are required for rotenone-induced apoptosis in SH-SY5Y cells (K. Newhouse et al., 2004, Toxicol. Sci. 79, 137-146) as well as primary neurons, and for paraquat-induced apoptosis in PC12 cells. However, JNK but not p38 plays a role in paraquat-induced loss of primary cultured dopaminergic neurons. Our data identify JNK activation as a common mechanism underlying dopaminergic cell death induced by both paraquat and rotenone in model cell lines and primary cultures.
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PMID:Activation of c-Jun N-terminal protein kinase is a common mechanism underlying paraquat- and rotenone-induced dopaminergic cell apoptosis. 1732 51

Inhibition of astrocytic apoptosis has been regarded as a novel prospective strategy for treating neurodegenerative disorders such as Parkinson's disease. In the present study, we demonstrated that iptakalim (IPT), an ATP-sensitive potassium channel (K(ATP) channel) opener, exerted protective effect on MPP(+)-induced astrocytic apoptosis, which was reversed by selective mitochondrial K(ATP) channel blocker 5-hydroxydecanoate. Further study revealed that IPT inhibited glutathione (GSH) depletion, mitochondrial membrane potential loss and subsequent release of pro-apoptotic factors (cytochrome c and apoptosis-inducing factor (AIF), and c-Jun NH(2)-terminal kinase/mitogen-activated protein kinases (MAPK) phosphorylation induced by MPP(+). Meanwhile, extracellular signal-regulated kinase (ERK) 1/2 inhibitor PD98059 inhibited the protective effect of IPT on MPP(+)-induced astrocytic apoptosis. Furthermore, IPT could also activate ERK/MAPK and maintain increased phospho-ERK1/2 level after MPP(+) exposure. Taken together, these findings reveal for the first time that IPT protects against MPP(+)-induced astrocytic apoptosis via inhibition of mitochondria apoptotic pathway and regulating the MAPK signal transduction pathways by opening mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels in astrocytes. And targeting K(ATP) channels expressed in astrocytes may provide a novel therapeutic strategy for neurodegenerative disorders.
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PMID:ATP-sensitive potassium channel opener iptakalim protects against MPP-induced astrocytic apoptosis via mitochondria and mitogen-activated protein kinase signal pathways. 1763 69

Anti-inflammatory strategies have attracted much interest for their potential to prevent further deterioration of Parkinson's disease. Recent experimental and clinical evidence indicate that statins - extensively used in medical practice as effective lipid-lowering agents - have also anti-inflammatory effects. In this study, we investigated the influence of simvastatin on the degenerative process of the dopaminergic neurons of the rat following intranigral injection of lipopolysaccharide (LPS), a potent inductor of inflammation that we have previously used as an animal model of Parkinson's disease. We evaluated TH positive neurons, astroglial, and microglial populations and found that simvastatin prevented the inflammatory processes, as the induction of interleukin-1beta, tumor necrosis factor-alpha, and iNOS and the consequent dopaminergic degeneration induced by LPS. Moreover, simvastatin produced the activation of the neurotrophic factor BDNF, along with the prevention of the oxidative damage to proteins. Moreover, it also prevents the main changes produced by LPS on different mitogen-activated protein kinases, featured as increases of P-c-Jun N-terminal protein kinase, P-extracellular signal-regulated kinase, p-38, and P-glycogen synthase kinase and the decrease of the promotion of cell survival signals such as cAMP response element-binding protein and Akt. Our results suggest that statins could delay the progression of dopaminergic degeneration in disorders involving inflammatory processes.
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PMID:Simvastatin prevents the inflammatory process and the dopaminergic degeneration induced by the intranigral injection of lipopolysaccharide. 1804 62

The signaling pathways which contribute to neuronal death during development, aging and disease have been extensively studied. While initial efforts focused on developmental death, increasing evidence suggests that mitogen-activated protein kinase pathways play a role in human pathology. In particular, the c-Jun N-terminal kinases (JNKs), mitogen-activated protein kinases activated by extracellular stimuli including stress, are a major focus. Knock-out mouse studies have demonstrated that removing particular JNK genes can reduce the severity in various disease scenarios, including those which are used to model Parkinson's disease and cerebral ischemia. In addition, activation of JNKs can be seen in human disease tissue. In this review we bring together the evidence for JNK being an important regulator of neuronal loss and outline the advancement of small molecule inhibitors for future therapeutic intervention.
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PMID:MAP kinase pathways in neuronal cell death. 1828 35

Histamine H(2) receptor antagonists have been reported to improve the motor symptoms of Parkinson's disease (PD) patients and to exert neuroprotective effects. In this study, we investigated the protective effects of the H(2) receptor antagonist ranitidine on rotenone-induced apoptosis in human dopaminergic SH-SY5Y cells, focusing on mitogen-activated protein kinases (MAPKs) and caspases (CASPs)-mediated apoptotic events. Ranitidine blocked the rotenone-induced phosphorylation of c-Jun NH(2)-terminal protein kinase (JNK) and P38 MAPK (P38), and promoted the phosphorylation of extracellular signal-regulated protein kinase (ERK). Ranitidine also prevented the down-regulation of B-cell CLL/lymphoma 2 (BCL2) and the up-regulation of BCL2-associated X protein (BAX) by rotenone. Furthermore, ranitidine not only attenuated rotenone-induced cleavages of CASP9, poly(ADP-ribose) polymerase-1 (PARP) and CASP3, but also suppressed CASP3 enzyme activity. These results indicate that ranitidine protects against rotenone-induced apoptosis, inhibiting phosphorylation of JNK and P38, and activation of CASPs in human dopaminergic SH-SY5Y cells.
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PMID:Protective effect of histamine H2 receptor antagonist ranitidine against rotenone-induced apoptosis. 1972 37


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