scholarly journals Effects of bacterial lipopolysaccharide exposure on immune responsiveness in a rodent model of Parkinson’s disease

2011 ◽  
Vol 63 (1) ◽  
pp. 99-105
Author(s):  
L. Hritcu ◽  
M. Stefan ◽  
Costica Misaila ◽  
A. Ciobica ◽  
Gabriela Dumitru
Keyword(s):  
Risk Factor ◽  
T Lymphocytes ◽  
Substantia Nigra ◽  
Immune Modulation ◽  
Hemoglobin Level ◽  
Immune Responsiveness ◽  
Unilateral Lesion ◽  
Blastic Transformation ◽  
Immunological Changes ◽  
6 Hydroxydopamine

The effects of lipopolysaccharide (LPS) on immune modulation in rats subjected to a right-unilateral lesion of the substantia nigra neurons by means of 6-hydroxydopamine (6-OHDA), were investigated. LPS administration (250 ?g) significantly decreases the total number of leukocytes and erythrocytes, as well as the hemoglobin level in the 6-OHDAlesioned rats. In addition, LPS administration was also associated with an increase, relative to control, in the erythrocyte indexes and the phagocytosis by neutrophils, and in blastic transformation of T lymphocytes. The obtained data indicated that LPS exposure might represent a risk factor for the development of the immunological changes associated with Parkinson?s disease.

scholarly journals Neuroinflammation and protein pathology in Parkinson’s disease dementia

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Antonina Kouli ◽  
Marta Camacho ◽  
Kieren Allinson ◽  
Caroline H. Williams-Gray
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
T Lymphocytes ◽  
Substantia Nigra ◽  
Amyloid Β ◽  
Brain Regions ◽  
Parkinson’S Disease Dementia ◽  
Activated Microglia ◽  
Cell Counts ◽  
The Brain

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.

scholarly journals Immune regulation of in vitro murine megakaryocyte development. Role of T lymphocytes and Ia antigen expression.

1985 ◽  
Vol 162 (6) ◽  
pp. 2053-2067 ◽  
Author(s):  
M W Long ◽  
D N Shapiro
Keyword(s):  
Cell Cycle ◽  
T Cell ◽  
T Lymphocytes ◽  
Progenitor Cells ◽  
Immune Modulation ◽  
Immune Recognition ◽  
Activated T Cells ◽  
Ia Antigen ◽  
Cell Cycle Status

Mitogen-activated murine T lymphocytes or T cell hybridomas produce an activity (megakaryocyte [Mk] potentiator activity) that enhances the in vitro growth and development of Mk colonies. This activity was found in optimal concentrations (2.5%) in T cell hybridoma-conditioned medium, and was also produced by feeder layers of concanavalin A-activated T cells. A subpopulation of murine Mk progenitor cells (colony-forming units; CFU-Mk) bears the Ia antigen. Separate experiments indicated that T cell products stimulate CFU-Mk by increasing their basal levels of Ia expression as well as the frequency of cells actively synthesizing DNA. The hypothesis that the expression of this antigen was related to the cell cycle status of these progenitor cells was confirmed in studies that indicated that ablation of actively cycling cells in vivo abrogated the cytotoxic effects of anti-Ia monoclonal antibodies. The interdependence of T cell lymphokine regulation of both Ia expression and cell cycle status was also seen in in vitro experiments in which Ia+ progenitor cells were eliminated by complement-dependent cytotoxicity. The removal of Ia+ cells prevented 5-hydroxyurea-mediated inhibition of cells in S phase. We hypothesize that immune modulation of megakaryocytopoiesis occurs via soluble T cell products that augment Mk differentiation. Further, the mechanism of immune recognition/modulation may occur via Ia antigens present on the surface of these progenitor cells.

Mildronate as a Regulator of Protein Expression in a Rat Model of Parkinson’s Disease

Medicina ◽  
2011 ◽  
Vol 47 (10) ◽  
pp. 79 ◽  
Author(s):  
Sergejs Isajevs ◽  
Darja Isajeva ◽  
Ulrika Beitnere ◽  
Baiba Jansone ◽  
Ivars Kalvinsh ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Growth Factor ◽  
Substantia Nigra ◽  
Rat Model ◽  
Control Group ◽  
Western Blot Assay ◽  
Neural Cell Adhesion ◽  
6 Hydroxydopamine ◽  
Cardioprotective Drug

Background. Mildronate (3-[2,2,2-trimethylhydrazinium] propionate dihydrate) traditionally is a well-known cardioprotective drug. However, our recent studies convincingly demonstrated its neuroprotective properties. The aim of the present study was to evaluate the influence of mildronate on the expression of proteins that are involved in the differentiation and survival of the nigrostriatal dopaminergic neurons in the rat model of Parkinson’s disease (PD). The following biomarkers were used: heat shock protein 70 (Hsp70, a molecular chaperone), glial cell line-derived nerve growth factor (GDNF, a growth factor promoting neuronal differentiation, regeneration, and survival), and neural cell adhesion molecule (NCAM). Material and Methods. PD was modeled by 6-hydroxydopamine (6-OHDA) unilateral intrastriatal injection in rats. Mildronate was administered at doses of 10, 20, and 50 mg/kg for 2 weeks intraperitoneally before 6-OHDA injection. Rat brains were dissected on day 28 after discontinuation of mildronate injections. The expression of biomarkers was assessed immunohistochemically and by Western blot assay. Results. 6-OHDA decreased the expression of Hsp70 and GDNF in the lesioned striatum and substantia nigra, whereas in mildronate-pretreated (20 and 50 mg/kg) rats, the expression of Hsp70 and GDNF was close to the control group values. NCAM expression also was decreased by 6-OHDA in the striatum and it was totally protected by mildronate at a dose of 50 mg/kg. In contrast, in the substantia nigra, 6-OHDA increased the expression of NCAM, while mildronate pretreatment (20 and 50 mg/kg) reversed the 6-OHDA-induced overexpression of NCAM close to the control values. Conclusion. The obtained data showed that mildronate was capable to regulate the expression of proteins that play a role in the homeostasis of neuro-glial processes.

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