epidermal-growth-factor and Parkinson-Disease

Topics: Animals; Basal Ganglia; Cats; Cattle; Cerebral Cortex; Cholinergic Fibers; Corpus Striatum; Dopamine; Enkephalin, Methionine; Epidermal Growth Factor; gamma-Aminobutyric Acid; Globus Pallidus; Haplorhini; Humans; Interneurons; Limbic System; Mice; Nerve Tissue Proteins; Neural Pathways; Neurotransmitter Agents; Parkinson Disease; Rats; Substance P; Substantia Nigra; Thalamic Nuclei

Interleukin (IL)-1 beta , IL-2, IL-4, IL-6, epidermal growth factor (EGF), and transforming growth factor (TGF)-alpha were measured for the first time in ventricular cerebrospinal fluid (VCSF) from control non-parkinsonian patients, patients with juvenile parkinsonism (JP) and patients with Parkinson's disease (PD) by highly sensitive sandwich enzyme immunoassays. All cytokines were detectable in VCSF from control and parkinsonian patients, and the concentrations were much higher than those in lumbar CFS. The concentrations of IL-1 beta, IL-2, IL-4 and TGF-alpha in VCSF were higher in JP than those in controls (P < 0.05). In contrast, the concentrations of IL-2 and IL-6 in VCSF from patients with PD were higher than those from control patients (P < 0.05). These results agree with our previous reports, in which the cytokine levels were elevated in the striatal dopaminergic region of the brain from patients with PD. Since VCSF is produced in the ventricles, the alteration of cytokines in VCSF may reflect the changes of cytokines in the brain. Because cytokines play an important role as mitogens and neurotrophic factors in the brain, the increases in cytokines as a compensatory response may occur in the brain of patients of JP or PD during the progress of neurodegeneration. Increase in cytokines may contribute not only as a compensatory response but as a primary initiating trigger for the neurodegeneration.

Topics: Adolescent; Adult; Age of Onset; Aged; Cerebral Ventricles; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Female; Humans; Interleukins; Male; Middle Aged; Mitogens; Nerve Degeneration; Parkinson Disease; Transforming Growth Factor alpha; Tumor Necrosis Factor-alpha

Insulin-like growth factor 1 (IGF-1) and epidermal growth factor (EGF) exert neuroprotective effects in Parkinson's disease (PD). To date, studies on the relationships between serum IGF-1 and EGF levels and nonmotor symptoms in PD patients have been rare.. A Siemens automatic chemical analyzer was used to determine serum IGF-1 levels, and enzyme-linked immunosorbent assay was used to detect serum EGF levels in 100 healthy controls and 100 PD patients, including those in the early (n = 49) and middle-late (n = 51) stage of the disease. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales.. Serum IGF-1 and EGF levels were higher in PD patients than in healthy controls, and serum IGF-1 and EGF levels were higher in early stage PD patients than in middle-late stage PD patients. Serum IGF-1 levels were significantly negatively correlated with anxiety, depression, and cognitive dysfunction; serum EGF levels were significantly negatively correlated with cognitive dysfunction. Combining IGF-1 and EGF in the diagnosis of PD was more valuable than using a single factor in the diagnosis.. This study shows that serum IGF-1 levels were correlated with the nonmotor symptoms of anxiety, depression, and cognitive dysfunction and that EGF levels were correlated with cognitive dysfunction. The combination of IGF-1 and EGF increased the value for a PD diagnosis. This is the first report of the simultaneous detection of IGF-1 and EGF levels to explore the correlation with nonmotor symptoms of PD.

Topics: Cognition; Cognitive Dysfunction; Epidermal Growth Factor; Humans; Insulin-Like Growth Factor I; Parkinson Disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by the loss of nigrostriatal dopaminergic (DAergic) neurons and the depletion of striatal dopamine. Here we show that DAergic-neuron-like cells could be efficiently induced from stem cells derived from human exfoliated deciduous teeth (SHEDs), and that these induced cells had therapeutic benefits in a 6-OHDA-induced Parkinsonian rat model. In our protocol, EGF and bFGF signaling activated the SHED's expression of proneural genes, Ngn2 and Mash1, and subsequent treatment with brain-derived neurotrophic factor (BDNF) promoted their maturation into DAergic neuron-like SHEDs (dSHEDs). A hypoxic DAergic differentiation protocol improved cell viability and enhanced the expression of multiple neurotrophic factors, including BDNF, GDNF, NT-3, and HGF. Engrafted dSHEDs survived in the striatum of Parkinsonian rats, improved the DA level more efficiently than engrafted undifferentiated SHEDs, and promoted the recovery from neurological deficits. Our findings further suggested that paracrine effects of dSHEDs contributed to neuroprotection against 6-OHDA-induced neurodegeneration and to nigrostriatal tract restoration. In addition, we found that the conditioned medium derived from dSHEDs protected primary neurons against 6-OHDA toxicity and accelerated neurite outgrowth in vitro. Thus, our data suggest that stem cells derived from dental pulp may have therapeutic benefits for PD.

Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Brain-Derived Neurotrophic Factor; Cell Differentiation; Cell Survival; Child; Dopaminergic Neurons; Epidermal Growth Factor; Fibroblast Growth Factor 2; Humans; Nerve Tissue Proteins; Neural Stem Cells; Parkinson Disease; Rats; Tooth, Deciduous

Topics: alpha-Synuclein; Biomarkers; Disease Progression; Epidermal Growth Factor; Humans; Parkinson Disease

Epidermal growth factor (EGF) has been proposed as a candidate biomarker for cognitive impairment in Parkinson's disease (PD). We aimed to assess the relationship between serum EGF and cognitive functions in early, drug-naive PD patients and evaluate the predictive value of EGF on cognitive functions in a 2-year follow-up study. Serum EGF was measured in 65 early, drug-naive PD patients, that underwent a comprehensive neuropsychological battery. Motor symptoms were assessed by means of the Unified Parkinson's Disease Rating Scale, Part III (UPDRS-III). Neuropsychological evaluation was repeated after 2 years. Spearman's rank correlation was used to assess the relationship between serum EGF levels and neuropsychological variables. Linear regression analysis was used to evaluate the relationship between EGF and neuropsychological scores as well as other variables (age, gender, UPDRS-III, levodopa equivalent dose, and type of treatment at follow-up) potentially affecting cognitive performance. Variation over time in cognitive scores was analyzed using repeated-measures ANOVA. At baseline, EGF was the only significant variable associated with performance on semantic fluency (R (2) = 0.131; p = 0.005). EGF levels (p = 0.025), together with UPDRS-III (p = 0.009) and age (p = 0.011), were associated with performance on frontal assessment battery (R (2) = 0.260). At 2-year follow-up, EGF was the only significant variable to predict performance on semantic fluency (R (2) = 0.147; p = 0.025) and color naming task of Stroop color-word test (R (2) = 0.121; p = 0.044). Serum EGF levels are related to frontal and temporal cognitive functions in early, drug-naive PD patients and predict performance on frontal and posterior cognitive functions at 2-year follow-up. EGF is proposed as a potential serum biomarker for early cognitive impairment in PD.

Topics: Aged; Analysis of Variance; Cognition Disorders; Epidermal Growth Factor; Female; Humans; Magnetic Resonance Imaging; Male; Mental Status Schedule; Middle Aged; Neuropsychological Tests; Parkinson Disease; Predictive Value of Tests; Regression Analysis; Tomography, X-Ray Computed

Most people with Parkinson disease (PD) eventually develop cognitive impairment (CI). However, neither the timing of onset nor the severity of cognitive symptoms can be accurately predicted. We sought plasma-based biomarkers for CI in PD.. A discovery cohort of 70 PD patients was recruited. Cognitive status was evaluated with the Mattis Dementia Rating Scale-2 (DRS) at baseline and on annual follow-up visits, and baseline plasma levels of 102 proteins were determined with a bead-based immunoassay. Using linear regression, we identified biomarkers of CI in PD, that is, proteins whose levels correlated with cognitive performance at baseline and/or cognitive decline at follow-up. We then replicated the association between cognitive performance and levels of the top biomarker, using a different technical platform, with a separate cohort of 113 PD patients.. Eleven proteins exhibited plasma levels correlating with baseline cognitive performance in the discovery cohort. The best candidate was epidermal growth factor (EGF, p < 0.001); many of the other 10 analytes covaried with EGF across samples. Low levels of EGF not only correlated with poor cognitive test scores at baseline, but also predicted an 8-fold greater risk of cognitive decline to dementia-range DRS scores at follow-up for those with intact baseline cognition. A weaker, but still significant, relationship between plasma EGF levels and cognitive performance was found in an independent replication cohort of 113 PD patients.. Our data suggest that plasma EGF may be a biomarker for progression to CI in PD.

Topics: Aged; Apolipoproteins E; Biomarkers; Cognition; Cognition Disorders; Epidermal Growth Factor; Female; Genotype; Humans; Linear Models; Male; Middle Aged; Parkinson Disease; Predictive Value of Tests

Bone marrow-derived human mesenchymal stem cells (hMSCs) have shown promise in in vitro neuronal differentiation and in cellular therapy for neurodegenerative disorders, including Parkinson' disease. However, the effects of intracerebral transplantation are not well defined, and studies do not agreed on the optimal neuronal differentiation method. Here, we investigated three growth factor-based neuronal differentiation procedures (using FGF-2/EGF/PDGF/SHH/FGF-8/GDNF), and found all to be capable of eliciting an immature neural phenotype, in terms of cell morphology and gene/protein expression. The neuronal-priming (FGF-2/EGF) method induced neurosphere-like formation and the highest NES and NR4A2 expression by hMSCs. Transplantation of undifferentiated and neuronal-primed hMSCs into the striatum and substantia nigra of 6-OHDA-lesioned hemiparkinsonian rats revealed transient graft survival of 7 days, despite the reported immunosuppressive properties of MSCs and cyclosporine-immunosuppression of rats. Neither differentiation of hMSCs nor induction of host neurogenesis was observed at injection sites, and hMSCs continued producing mesodermal fibronectin. Strategies for improving engraftment and differentiation post-transplantation, such as prior in vitro neuronal-priming, nigral and striatal grafting, and co-transplantation of olfactory ensheathing cells that promote neural regeneration, were unable to provide advantages. Innate inflammatory responses (Iba-1-positive microglia/macrophage and GFAP-positive astrocyte activation and accumulation) were detected around grafts within 7 days. Our findings indicate that growth factor-based methods allow hMSC differentiation toward immature neuronal-like cells, and contrary to previous reports, only transient survival and engraftment of hMSCs occurs following transplantation in immunosuppressed hemiparkinsonian rats. In addition, suppression of host innate inflammatory responses may be a key factor for improving hMSC survival and engraftment.

Topics: Animals; Blotting, Western; Bone Marrow; Cell Differentiation; Cells, Cultured; Corpus Striatum; Disease Models, Animal; Epidermal Growth Factor; Fibroblast Growth Factor 2; Fibroblast Growth Factor 8; Fluorescent Antibody Technique; Glial Cell Line-Derived Neurotrophic Factor; Hedgehog Proteins; Humans; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Neurons; Parkinson Disease; Platelet-Derived Growth Factor; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

It is thought that the ability of human mesenchymal stem cells (hMSC) to deliver neurotrophic factors might be potentially useful for the treatment of neurodegenerative disorders. The aim of the present study was to characterize signals and/or molecules that regulate brain-derived neurotrophic factor (BDNF) protein expression/delivery in hMSC cultures and evaluate the effect of epigenetically generated BDNF-secreting hMSC on the intact and lesioned substantia nigra (SN). We tested 4 different culture media and found that the presence of fetal bovine serum (FBS) decreased the expression of BDNF, whereas exogenous addition of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) to serum-free medium was required to induce BDNF release (125 ± 12 pg/day/10⁶ cells). These cells were called hM(N)SC. Although the induction medium inhibited the expression of alpha smooth muscle actin (ASMA), an hMSC marker, and increased the nestin-positive subpopulation of hMSC cultures, the ability to express BDNF was restricted to the nestin-negative subpopulation. One week after transplantation into the SN, the human cells integrated into the surrounding tissue, and some showed a dopaminergic phenotype. We also observed the activation of Trk receptors for neurotrophic factors around the implant site, including the BDNF receptor TrkB. When we transplanted these cells into the unilateral lesioned SN induced by striatal injection of 6-hydroxydopamine (6-OHDA), a significant hypertrophy of nigral tyrosine hydroxylase (TH)(+) cells, an increase of striatal TH-staining and stabilization of amphetamine-induced motor symptoms were observed. Therefore, hMSC cultures exposed to the described induction medium might be highly useful as a vehicle for neurotrophic delivery to the brain and specifically are strong candidates for future therapeutic application in Parkinson's disease.

Topics: Actins; Animals; Brain Injuries; Brain-Derived Neurotrophic Factor; Cell Differentiation; Cell Proliferation; Cell Survival; Culture Media; Culture Media, Serum-Free; Epidermal Growth Factor; Epigenesis, Genetic; Fibroblast Growth Factor 2; Gene Expression; Humans; Intermediate Filament Proteins; Locomotion; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Methamphetamine; Nerve Tissue Proteins; Nestin; Neurons; Oxidopamine; Parkinson Disease; Rats; Rats, Sprague-Dawley; Receptor, trkB; Rotation; Substantia Nigra; Tyrosine 3-Monooxygenase

Cripto is a glycosylphosphatidylinositol-anchored coreceptor that binds Nodal and the activin type I (ALK)-4 receptor, and is involved in cardiac differentiation of mouse embryonic stem cells (mESCs). Interestingly, genetic ablation of cripto results in increased neuralization and midbrain dopaminergic (DA) differentiation of mESCs, as well as improved DA cell replacement therapy (CRT) in a model of Parkinson's disease (PD). In this study, we developed a Cripto specific blocking tool that would mimic the deletion of cripto, but could be easily applied to embryonic stem cell (ESC) lines without the need of genetic manipulation. We thus screened a combinatorial peptide library and identified a tetrameric tripeptide, Cripto blocking peptide (BP), which prevents Cripto/ALK-4 receptor interaction and interferes with Cripto signaling. Cripto BP treatment favored neuroectoderm formation and promoted midbrain DA neuron differentiation of mESCs in vitro and in vivo. Remarkably, Cripto BP-treated ESCs, when transplanted into the striatum of PD rats, enhanced functional recovery and reduced tumor formation, mimicking the effect of genetic ablation of cripto. We therefore suggest that specific blockers such as Cripto BP may be used to improve the differentiation of ESC-derived DA neurons in vitro and their engraftment in vivo, bringing us closer towards an application of ESCs in CRT.

Topics: Activin Receptors, Type I; Animals; Cell Differentiation; Disease Models, Animal; Embryonic Stem Cells; Epidermal Growth Factor; Membrane Glycoproteins; Mice; Neoplasm Proteins; Neurons; Oligopeptides; Parkinson Disease; Protein Binding; Rats; Reverse Transcriptase Polymerase Chain Reaction; Stem Cell Transplantation

A reduction in dopaminergic innervation of the subventricular zone (SVZ) is responsible for the impaired proliferation of its resident precursor cells in this region in Parkinson's disease (PD). Here, we show that this effect involves EGF, but not FGF2. In particular, we demonstrate that dopamine increases the proliferation of SVZ-derived cells by releasing EGF in a PKC-dependent manner in vitro and that activation of the EGF receptor (EGFR) is required for this effect. We also show that dopamine selectively expands the GFAP(+) multipotent stem cell population in vitro by promoting their self-renewal. Furthermore, in vivo dopamine depletion leads to a decrease in precursor cell proliferation in the SVZ concomitant with a reduction in local EGF production, which is reversed through the administration of the dopamine precursor levodopa (L-DOPA). Finally, we show that EGFR(+) cells are depleted in the SVZ of human PD patients compared with age-matched controls. We have therefore demonstrated a unique role for EGF as a mediator of dopamine-induced precursor cell proliferation in the SVZ, which has potential implications for future therapies in PD.

Topics: Aging; Animals; Cell Differentiation; Cell Proliferation; Dopamine; Enzyme Activation; Epidermal Growth Factor; ErbB Receptors; Female; Neurons; Parkinson Disease; Rats; Rats, Sprague-Dawley

Numerous studies have shown that abnormal motor behavior improves when neural progenitor cells (NPCs) are transplanted into animal models of neurodegeneration. The mechanisms responsible for this improvement are not fully understood. Indirect anatomical evidence suggests that attention of abnormal motor behavior is attributed, at least in part, to the secretion of trophic factors from the transplanted NPCs. However, there is little direct evidence supporting this hypothesis. Here we show that NPCs isolated from the subventricular zone (SVZ) of neonatal mice are highly teratogenic when transplanted into the neural tube of developing chick embryos and are neuroprotective for fetal dopaminergic neurons in culture because they release sonic hedgehog (Shh). In addition, the neuroprotective properties of NPCs can be exploited to promote better long-term survival of transplanted fetal neurons in an animal model of Parkinson's disease. Thus, cultured NPCs isolated from the SVZ can secrete at least one potent mitogen (Shh) that dramatically affects the fate of neighboring cells. This trait may account for some of the improvement in motor behavior often reported in animal models of neurodegeneration after transplantation of cultured NPCs that were isolated from the SVZ.

Topics: Animals; Antimetabolites; Blotting, Western; Bromodeoxyuridine; Cell Count; Cell Survival; Cells, Cultured; Chick Embryo; Culture Media, Conditioned; Dopamine; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Female; Hedgehog Proteins; Immunohistochemistry; Mice; Mice, Transgenic; Movement Disorders; Neurons; Oxidopamine; Parkinson Disease; Stem Cell Transplantation; Stem Cells; Sympatholytics; Trans-Activators

Embryonic stem (ES) cells have been suggested as candidate therapeutic tools for cell replacement therapy in neurodegenerative disorders. However, limitations for the use of these cells lie in our restricted knowledge of the molecular mechanisms involved in their specialized differentiation and in the risk of tumor formation. Recent findings suggest that the EGF-CFC protein Cripto is a key player in the signaling pathways controlling neural induction in ES cells. Here we show that in vitro differentiation of Cripto(-/-) ES cells results in increased dopaminergic differentiation and that, upon transplantation into Parkinsonian rats, they result in behavioral and anatomical recovery with no tumor formation. The use of knockout ES cells that can generate dopamine cells while eliminating tumor risk holds enormous potential for cell replacement therapy in Parkinson's disease.

Topics: Animals; Brain; Brain Neoplasms; Cell Differentiation; Dopamine; Embryo, Mammalian; Epidermal Growth Factor; Male; Oxidopamine; Parkinson Disease; Rats; Rats, Sprague-Dawley; Stem Cell Transplantation; Stem Cells; Stereotyped Behavior; Teratoma

Epidermal growth factor (EGF) is a member of a structurally related family containing heparin-binding EGF-like growth factor (HB-EGF) and transforming growth factor alpha (TGFalpha) that exerts neurotrophic activity on midbrain dopaminergic neurons. To examine neurotrophic abnormality in Parkinson's disease (PD), we measured the protein content of EGF, TGFalpha, and HB-EGF in post-mortem brains of patients with Parkinson's disease and age-matched control subjects. Protein levels of EGF and tyrosine hydroxylase were decreased in the prefrontal cortex and the striatum of patients. In contrast, HB-EGF and TGFalpha levels were not significantly altered in either region. The expression of EGF receptors (ErbB1 and ErbB2, but not ErbB3 or ErbB4) was down-regulated significantly in the same forebrain regions. The same phenomenon was mimicked in rats by dopaminergic lesions induced by nigral 6-hydroxydopamine infusion. EGF and ErbB1 levels in the striatum of the PD model were markedly reduced on the lesioned side, compared with the control hemisphere. Subchronic supplement of EGF in the striatum of the PD model locally prevented the dopaminergic neurodegeration as measured by tyrosine hydroxylase immunoreactivity. These findings suggest that the neurotrophic activity of EGF is maintained by afferent signals of midbrain dopaminergic neurons and is impaired in patients with Parkinson's disease.

Topics: Adrenergic Agents; Aged; Aged, 80 and over; Animals; Blotting, Western; Disease Models, Animal; Drug Interactions; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; ErbB Receptors; Female; Functional Laterality; Gene Expression Regulation; Heparin-binding EGF-like Growth Factor; Humans; Intercellular Signaling Peptides and Proteins; Male; Middle Aged; Neurons; Oxidopamine; Parkinson Disease; Phosphopyruvate Hydratase; Postmortem Changes; Rats; Rats, Wistar; Signal Transduction; Statistics, Nonparametric; Substantia Nigra; Transforming Growth Factor alpha; Tyrosine 3-Monooxygenase

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of the EGF-family of ligands signaling via the EGF-receptor tyrosine kinase. In the present study we show that HB-EGF which is expressed in close proximity of developing mesencephalic dopaminergic neurons promotes the survival of TH-positive neurons in vitro. The survival promoting effect of HB-EGF is mediated via astroglial cells and utilizes the MAPK as well as the Akt-signaling pathway. Most notably endogenous HB-EGF significantly contributes to the survival of TH-+ neurons in control cultures, suggesting a relevant developmental role of HB-EGF for dopaminergic neurons. These findings indicate that HB-EGF may be an important molecule for developing dopaminergic neurons of the ventral midbrain.

Topics: Animals; Antibodies; Astrocytes; Cell Survival; Cells, Cultured; Dopamine; Epidermal Growth Factor; ErbB Receptors; Female; Fetus; Heparin-binding EGF-like Growth Factor; Intercellular Signaling Peptides and Proteins; MAP Kinase Signaling System; Neurons; Parkinson Disease; Pregnancy; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Signal Transduction; Substantia Nigra

Since EGF is known to protect and stimulate the activity of dopaminergic neurons, an autoradiographic study of [125I]EGF binding sites was performed in the striatum and pallidal complex in parkinsonian syndromes. The analysis was performed on postmortem brain tissues of three control subjects, three patients with Parkinson's disease, and three patients with progressive supranuclear palsy, another parkinsonian syndrome in which dopaminergic neurons also degenerate. Since all six patients had been treated with L-Dopa, we also analyzed the effects of this drug in an animal model of Parkinson's disease. Quantitative analysis of [125I]EGF binding was performed on the brains of three control monkeys, nine monkeys rendered parkinsonian by MPTP intoxication, three of which were treated with L-Dopa. An increased density of [125I]EGF binding was observed at anterior levels in the dorsal striatum, but not in the pallidum, of patients with Parkinson's disease and progressive supranuclear palsy. [125I]EGF binding was unchanged in parkinsonian monkeys whether or not they had been treated with L-Dopa. The data suggest an increased expression of EGFRs in the striatum in chronic parkinsonian syndromes but not in acute models of the disease.

Topics: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; Aged; Aged, 80 and over; Animals; Basal Ganglia; Brain Diseases; Dopamine Agents; Epidermal Growth Factor; ErbB Receptors; Female; Humans; Immunohistochemistry; Iodine Radioisotopes; Macaca fascicularis; Male; Parkinson Disease; Supranuclear Palsy, Progressive; Tetrabenazine

Topics: Animals; Brain; Cells, Cultured; Epidermal Growth Factor; Ethics, Medical; Fetus; Humans; Nerve Regeneration; Neurons; Parkinson Disease; Rats; Retinal Ganglion Cells

Interleukin (IL)-1 beta, IL-6, epidermal growth factor (EGF), and transforming growth factor-alpha (TGF-alpha) were measured for the first time in the brain (caudate nucleus, putamen and cerebral cortex) from control and parkinsonian patients by highly sensitive sandwich enzyme immunoassays. The concentrations of IL-1 beta, IL-6, EGF, and TGF-alpha in the dopaminergic, striatal regions were significantly higher in parkinsonian patients than those in controls, whereas those in the cerebral cortex did not show significant differences between parkinsonian and control subjects. Since these cytokines and growth factors may play important roles as neurotrophic factors in the brain, the present results suggest that they may be produced as compensatory responses in the nigrostriatal dopaminergic regions in Parkinson's disease, and may be related, at least in part, to the process of neurodegeneration in Parkinson's disease.

Topics: Aged; Aged, 80 and over; Brain Chemistry; Caudate Nucleus; Cerebral Cortex; Dopamine; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Female; Humans; Interleukin-1; Interleukin-6; Male; Middle Aged; Nerve Tissue Proteins; Parkinson Disease; Putamen; Transforming Growth Factor alpha