52 research outputs found
Evaluating the SERCA2 and VEGF mRNAs as Potential Molecular Biomarkers of the Onset and Progression in Huntington's Disease
Abnormalities of intracellular Ca2+ homeostasis and signalling as well as the down-regulation
of neurotrophic factors in several areas of the central nervous system and in peripheral
tissues are hallmarks of Huntington\u2019s disease (HD). As there is no therapy for this hereditary,
neurodegenerative fatal disease, further effort should be made to slow the progression
of neurodegeneration in patients through the definition of early therapeutic interventions.
For this purpose, molecular biomarker(s) for monitoring disease onset and/or progression
and response to treatment need to be identified. In the attempt to contribute to the research
of peripheral candidate biomarkers in HD, we adopted a multiplex real-time PCR approach
to analyse the mRNA level of targeted genes involved in the control of cellular calcium homeostasis
and in neuroprotection. For this purpose we recruited a total of 110 subjects possessing
the HD mutation at different clinical stages of the disease and 54 sex- and agematched
controls. This study provides evidence of reduced transcript levels of sarco-endoplasmic
reticulum-associated ATP2A2 calcium pump (SERCA2) and vascular endothelial
growth factor (VEGF) in peripheral blood mononuclear cells (PBMCs) of manifest and premanifest
HD subjects. Our results provide a potentially new candidate molecular biomarker
for monitoring the progression of this disease and contribute to understanding some early
events that might have a role in triggering cellular dysfunctions in HD
Altered mRNA Editing and Expression of Ionotropic Glutamate Receptors after Kainic Acid Exposure in Cyclooxygenase-2 Deficient Mice
Kainic acid (KA) binds to the AMPA/KA receptors and induces seizures that result in inflammation, oxidative damage and neuronal death. We previously showed that cyclooxygenase-2 deficient (COX-2−/−) mice are more vulnerable to KA-induced excitotoxicity. Here, we investigated whether the increased susceptibility of COX-2−/− mice to KA is associated with altered mRNA expression and editing of glutamate receptors. The expression of AMPA GluR2, GluR3 and KA GluR6 was increased in vehicle-injected COX-2−/− mice compared to wild type (WT) mice in hippocampus and cortex, whereas gene expression of NMDA receptors was decreased. KA treatment decreased the expression of AMPA, KA and NMDA receptors in the hippocampus, with a significant effect in COX-2−/− mice. Furthermore, we analyzed RNA editing levels and found that the level of GluR3 R/G editing site was selectively increased in the hippocampus and decreased in the cortex in COX-2−/− compared with WT mice. After KA, GluR4 R/G editing site, flip form, was increased in the hippocampus of COX-2−/− mice. Treatment of WT mice with the COX-2 inhibitor celecoxib for two weeks decreased the expression of AMPA/KA and NMDAR subunits after KA, as observed in COX-2−/− mice. After KA exposure, COX-2−/− mice showed increased mRNA expression of markers of inflammation and oxidative stress, such as cytokines (TNF-α, IL-1β and IL-6), inducible nitric oxide synthase (iNOS), microglia (CD11b) and astrocyte (GFAP). Thus, COX-2 gene deletion can exacerbate the inflammatory response to KA. We suggest that COX-2 plays a role in attenuating glutamate excitotoxicity by modulating RNA editing of AMPA/KA and mRNA expression of all ionotropic glutamate receptor subunits and, in turn, neuronal excitability. These changes may contribute to the increased vulnerability of COX-2−/− mice to KA. The overstimulation of glutamate receptors as a consequence of COX-2 gene deletion suggests a functional coupling between COX-2 and the glutamatergic system
Analysis of ancestral and functionally relevant CD5 variants in systemic lupus erythematosus patients
OBJECTIVE: CD5 plays a crucial role in autoimmunity and is a well-established genetic risk factor of developing RA. Recently, evidence of positive selection has been provided for the CD5 Pro224-Val471 haplotype in East Asian populations. The aim of the present work was to further analyze the functional relevance of non-synonymous CD5 polymorphisms conforming the ancestral and the newly derived haplotypes (Pro224-Ala471 and Pro224-Val471, respectively) as well as to investigate the potential role of CD5 on the development of SLE and/or SLE nephritis.
METHODS: The CD5 SNPs rs2241002 (C/T; Pro224Leu) and rs2229177 (C/T; Ala471Val) were genotyped using TaqMan allelic discrimination assays in a total of 1,324 controls and 681 SLE patients of Spanish origin. In vitro analysis of CD3-mediated T cell proliferative and cytokine response profiles of healthy volunteers homozygous for the above mentioned CD5 haplotypes were also analyzed.
RESULTS: T-cell proliferation and cytokine release were significantly increased showing a bias towards to a Th2 profile after CD3 cross-linking of peripheral mononuclear cells from healthy individuals homozygous for the ancestral Pro224-Ala471 (CC) haplotype, compared to the more recently derived Pro224-Val471 (CT). The same allelic combination was statistically associated with Lupus nephritis.
CONCLUSION: The ancestral Ala471 CD5 allele confers lymphocyte hyper-responsiveness to TCR/CD3 cross-linking and is associated with nephritis in SLE patients
Parenting programs for underserved populations: Issues of scientific integrity and social justice
Research suggests that parenting programs are effective for preventing behavioral and emotional difficulties in children, but a lot more attention needs to be paid to issues of context and culture during the development, testing and implementation of these interventions. The views and needs of underserved and disenfranchised communities in the US and the Global South are often not taken into account for the development and testing of interventions. The successful implementation of evidence-based interventions for vulnerable children and families in underserved and marginalized communities requires careful consideration of how existing paradigms of prevention, evaluation, and implementation science impact issues of social justice and equity. This paper will describe how a team of parenting program researchers has been collaborating with their partners globally in generating local knowledge by balancing the need for rigorous scientific methods with issues of power. Authors from the U.S., Latin America, Africa and Southeast Asia draw on their experiences regarding challenges and successes with issues regarding study design and measurement, the transferability and adaptation of interventions, and the dissemination and implementation of different parenting interventions while placing communities at the center of their efforts through participatory methods. We describe innovative approaches that span the continuum of intervention development, adaptation, optimization, evaluation, implementation, and scale up of different parenting programs for vulnerable children and families across the world. We conclude by offering specific and pragmatic recommendations to increase access of culturally relevant and effective parenting programs in these communities
Changes in Dopamine Signalling Do Not Underlie Aberrant Hippocampal Plasticity in a Mouse Model of Huntington’s Disease
Altered dopamine receptor labelling has been demonstrated in presymptomatic and symptomatic Huntington's disease (HD) gene carriers, indicating that alterations in dopaminergic signalling are an early event in HD. We have previously described early alterations in synaptic transmission and plasticity in both the cortex and hippocampus of the R6/1 mouse model of Huntington's disease. Deficits in cortical synaptic plasticity were associated with altered dopaminergic signalling and could be reversed by D1- or D2-like dopamine receptor activation. In light of these findings we here investigated whether defects in dopamine signalling could also contribute to the marked alteration in hippocampal synaptic function. To this end we performed dopamine receptor labelling and pharmacology in the R6/1 hippocampus and report a marked, age-dependent elevation of hippocampal D1 and D2 receptor labelling in R6/1 hippocampal subfields. Yet, pharmacological inhibition or activation of D1- or D2-like receptors did not modify the aberrant synaptic plasticity observed in R6/1 mice. These findings demonstrate that global perturbations to dopamine receptor expression do occur in HD transgenic mice, similarly in HD gene carriers and patients. However, the direction of change and the lack of effect of dopaminergic pharmacological agents on synaptic function demonstrate that the perturbations are heterogeneous and region-specific, a finding that may explain the mixed results of dopamine therapy in HD
- …