Mutations in LRRK2 impair NF-κB pathway in iPSC-derived neurons

Background: Mutations in leucine-rich repeat kinase 2 (LRRK2) contribute to both familial and idiopathic forms of Parkinson's disease (PD). Neuroinflammation is a key event in neurodegeneration and aging, and there is mounting evidence of LRRK2 involvement in inflammatory pathways. In a previous study, we described an alteration of the inflammatory response in dermal fibroblasts from PD patients expressing the G2019S and R1441G mutations in LRRK2. Methods: Taking advantage of cellular reprogramming, we generated induced pluripotent stem cell (iPSC) lines and neurons thereafter, harboring LRRK2G2019S and LRRK2R1441G mutations. We used gene silencing and functional reporter assays to characterize the effect of the mutations. We examined the temporal profile of TNF alpha-induced changes in proteins of the NF-kappa B pathway and optimized western blot analysis to capture alpha-synuclein dynamics. The effects of the mutations and interventions were analyzed by two-way ANOVA tests with respect to corresponding controls. Results: LRRK2 silencing decreased alpha-synuclein protein levels in mutated neurons and modified NF-kappa B transcriptional targets, such as PTGS2 (COX-2) and TNFAIP3 (A20). We next tested whether NF-kappa B and alpha-synuclein pathways converged and found that TNF alpha modulated alpha-synuclein levels, although we could not detect an effect of LRRK2 mutations, partly because of the individual variability. Nevertheless, we confirmed NF-kappa B dysregulation in mutated neurons, as shown by a protracted recovery of I kappa B alpha and a clear impairment in p65 nuclear translocation in the LRRK2 mutants. Conclusions: Altogether, our results show that LRRK2 mutations affect alpha-synuclein regulation and impair NF-kappa B canonical signaling in iPSC-derived neurons. TNFa modulated alpha-synuclein proteostasis but was not modified by the LRRK2 mutations in this paradigm. These results strengthen the link between LRRK2 and the innate immunity system underscoring the involvement of inflammatory pathways in the neurodegenerative process in PDThis study is funded by grants from the Spanish Ministry of Economy and Competitiveness (MINECO), Fondo de Investigaciones Sanitarias PI15/00486, the European Commission FP7 Health -278871, and the Joint Program in Neurodegenerative Diseases AC 14/0041 (DAMNDPATHS) to RSP

iPS cell cultures from a Gerstmann-Straussler-Scheinker patient with the Y218N PRNP mutation recapitulate tau pathology

Gerstmann-Straussler-Scheinker (GSS) syndrome is a fatal autosomal dominant neurodegenerative prionopathy clinically characterized by ataxia, spastic paraparesis, extrapyramidal signs and dementia. In some GSS familiar cases carrying point mutations in the PRNP gene, patients also showed comorbid tauopathy leading to mixed pathologies. In this study we developed an induced pluripotent stem (iPS) cell model derived from fibroblasts of a GSS patient harboring the Y218N PRNP mutation, as well as an age-matched healthy control. This particular PRNP mutation is unique with very few described cases. One of the cases presented neurofibrillary degeneration with relevant Tau hyperphosphorylation. Y218N iPS-derived cultures showed relevant astrogliosis, increased phospho-Tau, altered microtubule-associated transport and cell death. However, they failed to generate proteinase K-resistant prion. In this study we set out to test, for the first time, whether iPS cell-derived neurons could be used to investigate the appearance of disease-related phenotypes (i.e, tauopathy) identified in the GSS patient

Early changes in hippocampal Eph receptors precede the onset of memory decline in mouse models of Alzheimer's disease

Synapse loss occurs early in Alzheimer's disease (AD) and is considered thebest pathological correlate of cognitive decline. Ephrins and Eph receptorsare involved in regulation of excitatory neurotransmission and play a rolein cytoskeleton remodeling. We asked whether alterations in Eph receptorscould underlie cognitive impairment in an AD mouse model overexpressinghuman amyloid-β protein precursor (hAβPP) with familialmutations (hAβPPswe-ind mice). We found that EphA4 and EphB2receptors were reduced in the hippocampus before the development of impairedobject recognition and spatial memory. Similar results were obtained inanother line of transgenic AβPP mice, Tg2576. A reduction in Ephreceptor levels was also found in postmortem hippocampal tissue frompatients with incipient AD. At the time of onset of memory decline inhAβPPswe-ind mice, no change in surface expression of AMPA orNMDA receptor subunits was apparent, but we found changes in Eph-receptordownstream signaling, in particular a decrease in membrane-associatedphosho-cofilin levels that may cause cytoskeletal changes and disruptedsynaptic activity. Consistent with this finding, Eph receptor activation incell culture increased phosho-cofilin levels. The results suggest thatalterations in Eph receptors may play a role in synaptic dysfunction in thehippocampus leading to cognitive impairment in a model of AD.Supported by SAF2005-05086, SAF2008-02342 (Ministry of Science), CIBERNED (Ministry of Health), Government of Navarra and UTE project FIMA. We also thank Government of Navarra and La Rioja for fellowships (AMS, LE).Peer reviewe

The relationship between coping style and psychological distress in people with head and neck cancer: a systematic review

Objective Individuals diagnosed with head and neck cancer (HNC) are at an elevated risk of experiencing psychological distress and a reduced quality of life. The aim of this review was to systematically examine and assess the quality of empirical evidence on the associations between coping mechanisms and psychological distress among people with HNC. Methods CINAHL, MEDLINE, PsycINFO, EMBASE and Web of Science were accessed to conduct this review. Studies were included if they used reliable and valid measures to investigate the relationship between coping style and psychological distress. Study quality was assessed and rated according to pre-set criteria, and showed variability in relation to selection methods. Results 12 studies (nine cross-sectional and three prospective designs) involving 1281 patients were reviewed. There was considerable heterogeneity in study samples and coping measures. Moderate to large associations between disengagement coping mechanisms (e.g. avoidance) and psychological distress were observed. Engagement coping strategies (e.g. direct action) were not consistently associated with psychological distress across studies. Conclusions Several studies observed a significant relationship between coping styles aimed at disengaging and distancing from cancer and increased psychological distress. To understand directionality of these associations and further develop an understanding of temporal features of the relationship between coping styles and distress, longitudinal designs could be used in future research

Additional file 5: of Mutations in LRRK2 impair NF-κB pathway in iPSC-derived neurons

Uncropped blots related to Fig. 6