Effects of Neurotensin on the Effects of Pain Stress in Rats with Neurotoxic Lesions to Serotoninergic Structures of the Substantia Nigra of the Brain

2014 ◽  
Vol 44 (8) ◽  
pp. 863-870
Author(s):  
N. P. Shugalev* ◽  
A. V. Stavrovskaya ◽  
N. G. Yamshchikova ◽  
A. S. Ol’shanskii ◽  
E. A. Kashirina
Author(s):  
Antonina Kouli ◽  
Marta Camacho ◽  
Kieren Allinson ◽  
Caroline H. Williams-Gray

AbstractParkinson’s disease dementia is neuropathologically characterized by aggregates of α-synuclein (Lewy bodies) in limbic and neocortical areas of the brain with additional involvement of Alzheimer’s disease-type pathology. Whilst immune activation is well-described in Parkinson’s disease (PD), how it links to protein aggregation and its role in PD dementia has not been explored. We hypothesized that neuroinflammatory processes are a critical contributor to the pathology of PDD. To address this hypothesis, we examined 7 brain regions at postmortem from 17 PD patients with no dementia (PDND), 11 patients with PD dementia (PDD), and 14 age and sex-matched neurologically healthy controls. Digital quantification after immunohistochemical staining showed a significant increase in the severity of α-synuclein pathology in the hippocampus, entorhinal and occipitotemporal cortex of PDD compared to PDND cases. In contrast, there was no difference in either tau or amyloid-β pathology between the groups in any of the examined regions. Importantly, we found an increase in activated microglia in the amygdala of demented PD brains compared to controls which correlated significantly with the extent of α-synuclein pathology in this region. Significant infiltration of CD4+ T lymphocytes into the brain parenchyma was commonly observed in PDND and PDD cases compared to controls, in both the substantia nigra and the amygdala. Amongst PDND/PDD cases, CD4+ T cell counts in the amygdala correlated with activated microglia, α-synuclein and tau pathology. Upregulation of the pro-inflammatory cytokine interleukin 1β was also evident in the substantia nigra as well as the frontal cortex in PDND/PDD versus controls with a concomitant upregulation in Toll-like receptor 4 (TLR4) in these regions, as well as the amygdala. The evidence presented in this study show an increased immune response in limbic and cortical brain regions, including increased microglial activation, infiltration of T lymphocytes, upregulation of pro-inflammatory cytokines and TLR gene expression, which has not been previously reported in the postmortem PDD brain.


Author(s):  
Vaibhav Walia ◽  
Ashish Gakkhar ◽  
Munish Garg

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.


Biomolecules ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 391 ◽  
Author(s):  
Margaux Teil ◽  
Marie-Laure Arotcarena ◽  
Emilie Faggiani ◽  
Florent Laferriere ◽  
Erwan Bezard ◽  
...  

Parkinson’s Disease (PD) is characterized both by the loss of dopaminergic neurons in the substantia nigra and the presence of cytoplasmic inclusions called Lewy Bodies. These Lewy Bodies contain the aggregated α-synuclein (α-syn) protein, which has been shown to be able to propagate from cell to cell and throughout different regions in the brain. Due to its central role in the pathology and the lack of a curative treatment for PD, an increasing number of studies have aimed at targeting this protein for therapeutics. Here, we reviewed and discussed the many different approaches that have been studied to inhibit α-syn accumulation via direct and indirect targeting. These analyses have led to the generation of multiple clinical trials that are either completed or currently active. These clinical trials and the current preclinical studies must still face obstacles ahead, but give hope of finding a therapy for PD with time.


Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 3920-3925 ◽  
Author(s):  
Qin Wang ◽  
Fang Du ◽  
Zhong-Ming Qian ◽  
Xiao Hu Ge ◽  
Li Zhu ◽  
...  

Hepcidin plays an essential role in maintaining normal iron homeostasis outside the brain. This recently discovered iron regulation hormone is predominantly expressed in the liver, and regulated by iron and hypoxia. As an antimicrobial peptide, this hormone is also elevated during infections and inflammation. In this study we investigated the expression of hepcidin mRNA and protein in different brain regions, including the cortex, hippocampus, striatum, and substantia nigra, and the effects of lipopolysaccharide (LPS) on the expression of hepcidin using quantitative real-time RT-PCR and immunofluorescence analysis. Our data provided further evidence for the existence of hepcidin in all the regions we examined. We also demonstrated for the first time that LPS administration by iv injection can regulate the expression of hepcidin mRNA and protein not only in peripheral organs such as the liver, but also in the brain. LPS induced a significant increase in the expression of hepcidin mRNA and protein in the cortex and substantia nigra, but not in the hippocampus and striatum, indicating a regionally specific regulation of LPS on hepcidin in the brain. The relevant mechanisms and the functions of hepcidin in the brain remain to be elucidated.


1992 ◽  
Vol 40 (6) ◽  
pp. 889-892 ◽  
Author(s):  
R Arai ◽  
Y Kojima ◽  
M Geffard ◽  
K Kitahama ◽  
T Maeda

We investigated the applicability of the pre-embedding immunoperoxidase technique to WGAapoHRP-Au retrograde tracing. After injection of the tracer into the substantia nigra of rat, the brain was fixed and cryostat sections were immunostained for dopamine. The sections were osmicated and silver-stained to amplify the colloidal gold particles. Products of both the immunoperoxidase staining and the silver staining could be detected and distinguished by electron microscopy at low magnification. The ultrastructure was so well preserved that synaptic characteristics could be investigated. Dopaminergic terminals were demonstrated to synapse with striatal neurons projecting to the substantia nigra.


1992 ◽  
Vol 68 (2) ◽  
pp. 409-420 ◽  
Author(s):  
José L. Venero ◽  
Antonio J. Herrera ◽  
Alberto Machado ◽  
Josefina Cano

The contents of dopamine (DA) and serotonin (5-HT) and their metabolites were measured in rat substantia nigra and corpus striatum following dietary changes, including restriction of protein content (low-protein diet; LPD) and the contents of several large neutral amino acids (isoleucine, leucine, methionine, phenylalanine, tryptophan and valine) for 25 d. The LPD produced an increase in the concentration of tyrosine (TYR) in the two regions of the brain studied. This effect was also observed with all amino acid deficiencies studied except for valine in the substantia nigra, tryptophan in the striatum and phenylalanine in both regions. Likewise, the concentration of 5-hydroxyindolacetic acid (5-HIAA), the main metabolite of 5-HT, increased in the substantia nigra but not in the striatum after LPD, as well as with all the amino acid deficiencies studied, with the exception of tryptophan deficiency. In this case there was a dramatic effect on all components of the serotoninergic system, with decreases in the concentration of tryptophan (TRP; precursor), 5-HT and 5-HIAA. This behaviour clearly shows an interrelationship between precursor (TRP) availability and 5-HT synthesis and metabolism. With valine deficiency, dopaminergic and serotoninergic systems demonstrated opposite effects in the substantia nigra and the corpus striatum, and the behaviour of the two monoamines was also opposite within each structure. The significance of these changes is discussed.


2019 ◽  
pp. S453-S458
Author(s):  
R. Krupička ◽  
S. Mareček ◽  
C. Malá ◽  
M. Lang ◽  
O. Klempíř ◽  
...  

Neuromelanin (NM) is a black pigment located in the brain in substantia nigra pars compacta (SN) and locus coeruleus. Its loss is directly connected to the loss of nerve cells in this part of the brain, which plays a role in Parkinson’s Disease. Magnetic resonance imaging (MRI) is an ideal tool to monitor the amount of NM in the brain in vivo. The aim of the study was the development of tools and methodology for the quantification of NM in a special neuromelanin-sensitive MRI images. The first approach was done by creating regions of interest, corresponding to the anatomical position of SN based on an anatomical atlas and determining signal intensity threshold. By linking the anatomical and signal intensity information, we were able to segment the SN. As a second approach, the neural network U-Net was used for the segmentation of SN. Subsequently, the volume characterizing the amount of NM in the SN region was calculated. To verify the method and the assumptions, data available from various patient groups were correlated. The main benefit of this approach is the observer-independency of quantification and facilitation of the image processing process and subsequent quantification compared to the manual approach. It is ideal for automatic processing many image sets in one batch.


2012 ◽  
Vol 26 (S1) ◽  
Author(s):  
Nandhini Kanagaraj ◽  
S Thameem Dheen ◽  
Zhao Feng Peng ◽  
Dinesh Kumar Srinivasan ◽  
Samuel S W Tay

2018 ◽  
Author(s):  
Pedro D. Maia ◽  
Sneha Pandya ◽  
Justin Torok ◽  
Ajay Gupta ◽  
Yashar Zeighami ◽  
...  

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.


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