Ocular Motor Disorders Caused by Lesions in the Cerebrum

2008 ◽  
Author(s):  
Agnes Wong
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Globus Pallidus ◽  
Neurodegenerative Disorder ◽  
Neuroprotective Effect ◽  
D2 Agonist ◽  
Intermediate Layers ◽  
Dorsolateral Prefrontal ◽  
Eye Field

■ Receives inputs from the frontal eye field (FEF), supplementary eye field (SEF), dorsolateral prefrontal cortex (DLPC), internal medullary lamina of the thalamus, and substantia nigra pars compacta (SNpc, the dopaminergic portion) ■ Projects to substantia nigra pars reticulata (SNpr) and the globus pallidus ■ Receives inhibitory inputs from the caudate nucleus ■ Sends inhibitory signals to intermediate layers of the superior colliculus Parkinson’s disease is a progressive neurodegenerative disorder that affects about 1% of adults over 60 years of age. 1. Loss of pigmented dopaminergic neurons in the SNpc 2. Presence of Lewy bodies (not specific for Parkinson’s disease) 3. Decreased dopamine reaching the striatum causes increased inhibitory output from the globus pallidus internal segment and SNpr, thereby inhibiting movement 1. Standard therapy: levadopa and carbidopa (a peripheral decarboxylase inhibitor to reduce motor fluctuations and dyskinesia) e.g., such as Sinemet or Sinemet CR 2. Monoamine oxidase-β inhibitor (e.g., Selegiline); may have neuroprotective effect 3. Dopamine agonist (e.g., bromocriptine, a D2 agonist, and apomorphine, a D1 and D2 agonist) 4. Anticholinergics (e.g., Benzhexol) 5. Amantadine (seldom used) 6. Surgery ■ Thalamotomy or thalamic deep brain stimulation of the ventral lateral nucleus to reduce medically refractory tremor. The mechanism of action is unknown; these procedures may destroy autonomous neural activity (synchronous bursts) that has the same frequency as the limb tremor. ■ Pallidotomy or pallidal stimulation to reduce contralateral dyskinesia (e.g., bradykinesia, rigidity, and tremor).

Neuroprotective Effects of a GLP-2 Analogue in the MPTP Parkinson’s Disease Mouse Model

2021 ◽  
pp. 1-15
Author(s):  
Zijuan Zhang ◽  
Li Hao ◽  
Ming Shi ◽  
Ziyang Yu ◽  
Simai Shao ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Mouse Model ◽  
Neurodegenerative Disorder ◽  
Enzyme Linked Immunosorbent Assay ◽  
Protective Effects ◽  
Neuroprotective Effects ◽  
Expression Levels ◽  
Dual Agonist

Background: Glucagon-like peptide 2 (GLP-2) is a peptide hormone derived from the proglucagon gene expressed in the intestines, pancreas and brain. Some previous studies showed that GLP-2 improved aging and Alzheimer’s disease related memory impairments. Parkinson’s disease (PD) is a progressive neurodegenerative disorder, and to date, there is no particular medicine reversed PD symptoms effectively. Objective: The aim of this study was to evaluate neuroprotective effects of a GLP-2 analogue in the 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) PD mouse model. Methods: In the present study, the protease resistant Gly(2)-GLP-2 (50 nmol/kg ip.) analogue has been tested for 14 days by behavioral assessment, transmission electron microscope, immunofluorescence histochemistry, enzyme-linked immunosorbent assay and western blot in an acute PD mouse model induced by MPTP. For comparison, the incretin receptor dual agonist DA5-CH was tested in a separate group. Results: The GLP-2 analogue treatment improved the locomotor and exploratory activity of mice, and improved bradykinesia and movement imbalance of mice. Gly(2)-GLP-2 treatment also protected dopaminergic neurons and restored tyrosine hydroxylase expression levels in the substantia nigra. Gly(2)-GLP-2 furthermore reduced the inflammation response as seen in lower microglia activation, and decreased NLRP3 and interleukin-1β pro-inflammatory cytokine expression levels. In addition, the GLP-2 analogue improved MPTP-induced mitochondrial dysfunction in the substantia nigra. The protective effects were comparable to those of the dual agonist DA5-CH. Conclusion: The present results demonstrate that Gly(2)-GLP-2 can attenuate NLRP3 inflammasome-mediated inflammation and mitochondrial damage in the substantia nigra induced by MPTP, and Gly(2)-GLP-2 shows neuroprotective effects in this PD animal model.

Potential neuroprotective effect of androst-5-ene-3β, 17β-diol (ADIOL) on the striatum, and substantia nigra in Parkinson's disease rat model

2018 ◽  
Vol 233 (8) ◽  
pp. 5981-6000 ◽  
Author(s):  
Rania M. Salama ◽  
Mariane G. Tadros ◽  
Mona F. Schaalan ◽  
Nevine Bahaa ◽  
Ahmed M. Abdel-tawab ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Rat Model ◽  
Neuroprotective Effect

scholarly journals Peptide TFP5/TP5 derived from Cdk5 activator P35 provides neuroprotection in the MPTP model of Parkinson’s disease

2015 ◽  
Vol 26 (24) ◽  
pp. 4478-4491 ◽  
Author(s):  
BK. Binukumar ◽  
Varsha Shukla ◽  
Niranjana D. Amin ◽  
Philip Grant ◽  
M. Bhaskar ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Neurodegenerative Disorder ◽  
Neuroprotective Effect ◽  
Selective Inhibition ◽  
Motor Dysfunction ◽  
Dopamine Neurons ◽  
Dopamine Depletion ◽  
Neuroprotective Effects

Parkinson’s disease (PD) is a chronic neurodegenerative disorder characterized by the loss of dopamine neurons in the substantia nigra, decreased striatal dopamine levels, and consequent extrapyramidal motor dysfunction. Recent evidence indicates that cyclin-dependent kinase 5 (Cdk5) is inappropriately activated in several neurodegenerative conditions, including PD. To date, strategies to specifically inhibit Cdk5 hyperactivity have not been successful without affecting normal Cdk5 activity. Previously we reported that TFP5 peptide has neuroprotective effects in animal models of Alzheimer’s disease. Here we show that TFP5/TP5 selective inhibition of Cdk5/p25 hyperactivation in vivo and in vitro rescues nigrostriatal dopaminergic neurodegeneration induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP+) in a mouse model of PD. TP5 peptide treatment also blocked dopamine depletion in the striatum and improved gait dysfunction after MPTP administration. The neuroprotective effect of TFP5/TP5 peptide is also associated with marked reduction in neuroinflammation and apoptosis. Here we show selective inhibition of Cdk5/p25 ­hyperactivation by TFP5/TP5 peptide, which identifies the kinase as a potential therapeutic target to reduce neurodegeneration in Parkinson’s disease.

Parkinson's Disease

2019 ◽  
pp. 252-273 ◽  
Author(s):  
Vaibhav Walia ◽  
Ashish Gakkhar ◽  
Munish Garg
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Dopaminergic Neurons ◽  
Older Patients ◽  
Neurodegenerative Disorder ◽  
Progressive Loss ◽  
The Brain

Parkinson's disease (PD) is a neurodegenerative disorder in which a progressive loss of the dopaminergic neurons occurs. The loss of the neurons is most prominent in the substantia nigra region of the brain. The prevalence of PD is much greater among the older patients suggesting the risk of PD increases with the increase of age. The exact cause of the neurodegeneration in PD is not known. In this chapter, the authors introduce PD, demonstrate its history, pathogenesis, neurobiology, sign and symptoms, diagnosis, and pharmacotherapy.

Neurotoxicity risk assessment of MPTP (N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) as a synthetic impurity of drugs

1998 ◽  
Vol 17 (5) ◽  
pp. 283-293 ◽  
Author(s):  
Peter Juergen Kramer ◽  
John Caldwell ◽  
Andreas Hofmann ◽  
Peter Tempel ◽  
Guenter Weisse
Keyword(s):  
Risk Assessment ◽  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Health Risk ◽  
Globus Pallidus ◽  
Dopaminergic Neurons ◽  
Idiopathic Parkinson's Disease ◽  
Candidate Drug ◽  
A Minor

1-Methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) induces symptoms indistinguishable from those of Parkinson's disease. It selectively destroys dopaminergic neurons in the substantia nigra and the globus pallidus. Death of these same neurons is apparently the cause of idiopathic Parkinson's disease. As phenyl-1,2,3,6 tetrahydropyridine is a commonly encountered subunit in heterocyclic drugs and because MPTP was found as a minor impurity in early batches of a candidate drug at Merck KGaA, it may be assumed that MPTP will also be present as an as yet undiscovered minor impurity in various existing drugs. A neurotoxicity risk assessment on MPTP has been conducted to define the risk of MPTP as an impurity in drugs that are used orally. This risk assessment has shown that compounds containing less than 5.0 p.p.m. MPTP administered orally will not cause a neurotoxicological health risk to patients treated with such a drug.

scholarly journals Effects of Hypericum perforatum on turning behavior in an animal model of Parkinson's disease

2015 ◽  
Vol 51 (1) ◽  
pp. 111-115 ◽  
Author(s):  
Débora Dalla Vecchia ◽  
Marissa Giovanna Schamne ◽  
Marcelo Machado Ferro ◽  
Ana Flávia Chaves dos Santos ◽  
Camila Lupepsa Latyki ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Animal Model ◽  
Hypericum Perforatum ◽  
Neurodegenerative Disorder ◽  
Neuroprotective Effect ◽  
Turning Behavior ◽  
Age Related ◽  
Lesion Side ◽  
6 Hydroxydopamine

Parkinson's disease (PD) is an age-related neurodegenerative disorder characterized by the slow and progressive death of dopaminergic neurons in the (substantia nigra pars compact). Hypericum perforatum (H. perforatum) is a plant widely used as an antidepressant, that also presents antioxidant and anti-inflammatory properties. We evaluated the effects of H. perforatum on the turning behavior of rats submitted to a unilateral administration of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle as an animal model of PD. The animals were treated with H. perforatum (100, 200, or 400 mg/kg, v.o.) for 35 consecutive days (from the 28th day before surgery to the 7th day after). The turning behavior was evaluated at 7, 14 and 21 days after the surgery, and the turnings were counted as contralateral or ipsilateral to the lesion side. All tested doses significantly reduced the number of contralateral turns in all days of evaluation, suggesting a neuroprotective effect. However, they were not able to prevent the 6-OHDA-induced decrease of tyrosine hydroxylase expression in the lesioned striatum. We propose that H. perforatum may counteract the overexpression of dopamine receptors on the lesioned striatum as a possible mechanism for this effect. The present findings provide new evidence that H. perforatum may represent a promising therapeutic tool for PD.

scholarly journals Heterogeneity of Incipient Atrophy Patterns in Parkinson’s Disease

2018 ◽  
Author(s):  
Pedro D. Maia ◽  
Sneha Pandya ◽  
Justin Torok ◽  
Ajay Gupta ◽  
Yashar Zeighami ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Neurodegenerative Disorder ◽  
Neuronal Loss ◽  
High Variability ◽  
Clinical Value ◽  
Optimization Routine ◽  
Penalized Optimization ◽  
The Brain

AbstractParkinson’s Disease (PD) is a the second most common neurodegenerative disorder after Alzheimer’s disease and is characterized by cell death in the amygdala and in substructures of the basal ganglia such as the substantia nigra. Since neuronal loss in PD leads to measurable atrophy patterns in the brain, there is clinical value in understanding where exactly the pathology emerges in each patient and how incipient atrophy relates to the future spread of disease. A recent seed-inference algorithm combining an established network-diffusion model with an L1-penalized optimization routine led to new insights regarding the non-stereotypical origins of Alzheimer’s pathologies across individual subjects. Here, we leverage the same technique to PD patients, demonstrating that the high variability in their atrophy patterns also translates into heterogeneous seed locations. Our individualized seeds are significantly more predictive of future atrophy than a single seed placed at the substantia nigra or the amygdala. We also found a clear distinction in seeding patterns between two PD subgroups – one characterized by predominant involvement of brainstem and ventral nuclei, and the other by more widespread frontal and striatal cortices. This might be indicative of two distinct etiological mechanisms operative in PD. Ultimately, our methods demonstrate that the early stages of the disease may exhibit incipient atrophy patterns that are more complex and variable than generally appreciated.

scholarly journals Role of Genes and Treatments for Parkinson’s Disease

2020 ◽  
Vol 8 (1) ◽  
pp. 47-65
Author(s):  
Falaq Naz ◽  
Yasir Hasan Siddique
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Dopaminergic Neurons ◽  
Autosomal Dominant ◽  
Neurodegenerative Disorder ◽  
Treatment Strategies ◽  
Number Of Genes ◽  
Permanent Cure

Parkinson’s Disease (PD) is a complex neurodegenerative disorder that mainly results due to the loss of dopaminergic neurons in the substantia nigra of the midbrain. It is well known that dopamine is synthesized in substantia nigra and is transported to the striatum via nigrostriatal tract. Besides the sporadic forms of PD, there are also familial cases of PD and number of genes (both autosomal dominant as well as recessive) are responsible for PD. There is no permanent cure for PD and to date, L-dopa therapy is considered to be the best option besides having dopamine agonists. In the present review, we have described the genes responsible for PD, the role of dopamine, and treatment strategies adopted for controlling the progression of PD in humans.

scholarly journals Susceptibility-weighted MR imaging (SWI) of basal ganglia iron deposition in the early and advanced stages of Parkinson's disease

2019 ◽  
Vol 11 (2) ◽  
pp. 30-36
Author(s):  
A. G. Trufanov ◽  
A. A. Yurin ◽  
A. B. Buriak ◽  
S. A. Sandalov ◽  
M. M. Odinak ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Substantia Nigra ◽  
Caudate Nucleus ◽  
Globus Pallidus ◽  
Red Nucleus ◽  
Regions Of Interest ◽  
Iron Deposition ◽  
Left Caudate

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease and the first one among the nosological entities of parkinsonism. Susceptibility-weighted imaging (SWI), magnetic resonance imaging (MRI) pulse sequence, which allows the in vivo estimation of the values of iron deposition in different areas of the brain, is a potential technique for the early diagnosis of PD and for the study of the pathogenesis of its complications.Objective: to compare the values of iron deposition in the basal ganglia in Stages II and III PD and to determine the relationship of clinical findings to the level of iron deposition according to the SWI findings.Patients and methods. Twenty-four patients with Hoehn and Yahr Stages II (n=24) and III (n=12) PD were examined. All the patients underwent brain MRI on a Siemens TrioTim (3T) MRI scanner by using pulse sequences T1, T2, SWI and subsequently quantifying the iron deposition (SPIN software). The accumulation of iron is visualized as an area of reduced signal intensity on SWI, and its estimation in accordance with the SPIN program has accordingly a smaller value. The regions of interest on both sides were the dentate nucleus, substantia nigra, red nucleus, putamen, globus pallidus, and head of the caudate nucleus. The examination protocol also included tests using the following scales: the Unified Parkinson's Disease Rating Scale (UPDRS), the Mini-Mental State Examination (MMSE), Frontal Assessment Batter (FAB), Freezing of Gait (FOG), Gait and Balance Scale (GABS), the Epworth Daytime Sleepiness Scale, the Parkinson's Disease Quality of Life Questionnaire (PDQ), the Beck Depression Inventory, and the Clock-Drawing Test.Results and discussion. The investigators found significant (p<0.05) correlations between the clinical picture and the level of iron deposition in the regions of interest in patients with Stage II PD: FOG – left caudate nucleus (r=-0.94); GABS – left caudate nucleus (r=-0.94); and in patients with stage III of the disease: UPDRS (full) – left red nucleus (r=-0.82), right globus pallidus (r=-0,80), left putamen (r=-0,96); UPDRS (Section 2) – left red nucleus (r=-0.77), left globus pallidus (r=-0.84); UPDRS (Section 3) – right putamen (r=-0,85), right globus pallidus (r=-0.78), left globus pallidus (r=-0,92); FOG – left globus pallidus (r=-0.81); GABS – left red nucleus (r=-0.96), left putamen (r=0.82), right putamen (r=-0.89), left globus pallidus (r=-0.82), right globus pallidus (r=-0.85), left caudate nucleus (r=-0.82), right caudate nucleus (r=-0.89); Beck Depression Inventory – right substantia nigra (r=-0.82).Conclusion. SWI measurement of the values of iron deposition in the structures of the extrapyramidal system in PD provides an additional insight into the pathological processes occurring in them.

scholarly journals Neuroprotective Effect of Ropinirole Lipid Nanoparticles Enriched Hydrogel for Parkinson’s Disease: In Vitro, Ex Vivo, Pharmacokinetic and Pharmacodynamic Evaluation

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 448 ◽  
Author(s):  
Narendar Dudhipala ◽  
Thirupathi Gorre
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Oral Administration ◽  
Neurodegenerative Disorder ◽  
Ex Vivo ◽  
Neuroprotective Effect ◽  
Topical Delivery ◽  
Lipid Nanoparticles ◽  
Oral Dosage

Parkinson’s disease (rp) is a progressive neurodegenerative disorder. Ropinirole (RP) is a newer generation dopamine agonist used for the treatment of PD. It is prescribed as oral dosage form. However, limited oral bioavailability and frequent dosing limits the RP usage. The objective of the current investigation was to develop, optimize, evaluate pharmacokinetic (PK) and pharmacodynamic (PCD) activity of RP loaded solid lipid nanoparticles (RP-SLNs) and nanostructured lipid carriers (RP-NLCs) and containing hydrogel (RP-SLN-C and RP-NLC-C) formulations for improved oral and topical delivery. RP loaded lipid nanoparticles were optimized and converted to hydrogel using carbopol 934 as the gelling polymer. PK and PCD studies in haloperidol-induced PD were conducted in male Wistar rats. In vitro and ex vivo permeation studies showed sustained release profile and enhanced permeation compared with control formulations. Differential scanning calorimeter and X-ray diffraction studies revealed amorphous transformation; scanning electron microscope showed the spherical shape of RP in lipid nanoparticles. PK studies showed 2.1 and 2.7-folds enhancement from RP-SLN and RP-NLC from oral administration, 3.0 and 3.3-folds enhancement from RP-SLN-C and RP-NLC-C topical administration, compared with control formulations, respectively. RP-SLN-C and RP-NLC-C showed 1.4 and 1.2-folds topical bioavailability enhancement compared with RP-SLN and RP-NLC oral administration, respectively. PCD studies showed enhanced dopamine, glutathione, catalase levels and reduced lipid peroxidation levels, compared with the haloperidol-induced PD model. Overall, the results demonstrated that lipid nanoparticles and corresponding hydrogel formulations can be considered as an alternative delivery approach for the improved oral and topical delivery of RP for the effective treatment of PD.

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