Neurochemical characterization of basal ganglia neuropeptides and proteins in levodopa-induced dyskinesia in experimental Parkinson’s disease using Imaging Mass Spectrometry and Peptidomics

Per Andrén, Anna Nilsson, Patrik Källback, Maria Fälth, Henrik Wadensten, MMS, Per Svenningsson, Karolinska Institutet, Alan Crossman, University of Manchester, UK, Erwan Bezard, Univ. of Bordeaux 2, France.

The main objective of the present research is to study neurochemical processes in Parkinson disease and specifically L-Dopa-induced dyskinesias (LID). No treatment exists yet for the management of LID, a debilitating complication of L-dopa therapy for PD. The aim is to define neuropeptides and proteins that are differentially expressed in the basal ganglia complex of animals with striatal dopamine depletions, with and without LID.

Integration of resources and studies to elucidate neuropeptide signaling

Per Andrén, Anna Nilsson, Maria Fälth, MMS, Jonathan Sweedler and Sandra Rodrigues-Zas, University of Illinois Urbana-Champaign, IL, USA

We propose to develop a public and comprehensive neuropeptide resource much needed by the research community by collectively analyzing proteomic and transcriptomic experiments to augment the understanding of extracellular signaling peptides both at the fundamental neuroscience as well as the applied substance abuse levels. To accomplish these objectives, we plan to integrate complementary peptide repositories and develop tools to assemble and effectively query a comprehensive and public resource of experimental and in silico predictions; mine this resource to perform secondary and joint analysis of available high proteomic experiments; and perform integrated analysis of proteomic and transcriptomic experiments. The overarching strategy is to integrate complementary information across databases, experiments and platforms to provide a unique and comprehensive understanding of the dynamic neuropeptide complement. The outcome of this project will be resources, tools and information that will fill critical gaps in the knowledge on intercellular signaling systems.

Identification and functional characterization of protein-protein interactions in cerebrospinal fluid and brain tissue from Parkinson’s disease (PD) patients and experimental PD models

Per Andrén, Anna Nilsson, MMS, Per Svenningsson, Karolinska Institutet, Peter Verhaert, University of Delft, the Netherlands

Using surface plasmon resonance technique (Biacore 3000) coupled to mass spectrometry technology, new protein partners of α-synuclein and parkin have been captured and identified in cerebrospinal fluid or post-mortem human tissue from PD patients. In addition to using native α-synuclein and parkin, mutated forms of these proteins seen in familiar forms of PD will be immobilized on the sensor chip and used as baits.

Fine mapping the spatial distribution and concentration of unlabeled drugs within tissue micro-compartments using imaging mass spectrometry

Per Andrén, Anna Nilsson, MMS, AstraZeneca, Lund

In respiratory inhalation drug discovery projects, one key objective is to optimize retention of compound in the lung and consequently achieve duration of effect. Current technologies only provide information on the total amount of compound in the whole lung with no possibility to address microenvironmental localization of the compound or metabolic derivatives. The application of MALDI imaging mass spectrometry in such studies would provide a new tool to accurately measure local tissue concentrations of drug/drug metabolite in context with efficacy achieved with the targeted biology or in the context of safety. Such technology could provide new and important information.

Novel molecular imaging approaches for the development of new diagnostic tools for colon cancer and Alzheimer’s disease using Imaging Mass Spectrometry.

Per Andrén, Anna Nilsson, Henrik Wadensten, MMS, Bengt Långström, Department of Biochemistry & Organic Chemistry, and Uppsala Applied Science Lab, GE Healthcare, Håkan Hall, Uppsala Applied Science Lab, GE Healthcare, Lars Påhlman, Ulrik Wallin, Department of Surgery

This collaborative project aims at developing new methods for the clinical diagnosis of colon cancer and Alzheimer’s disease using molecular imaging leading aiming at finding new therapeutic avenues. Advanced biochemical, imaging mass spectrometry, cell culturing and imaging methods will be used in the search of new 68Ga-labeled tracers for the early diagnosis of colon cancer and Alzheimer’s disease with positron emission tomography.

Novel inactivation technology stabilizes the in vivo levels of proteins, peptides and phosphorylations in tissue samples

Per Andrén, Patrik Källback, Anna Nilsson, Henrik Wadensten, MMS, Per Svenningsson, Karolinska Institutet, Denator AB, Uppsala and Göteborg, Sweden

After tissue or blood sampling, proteases and other protein-modifying enzymes can rapidly change proteome composition. Subsequent analytical results reflect a mix of in vivo proteome and degradation products. Vital information about the ‘pre-sampling’ state may be destroyed or distorted, leading to variation between samples or even erroneous conclusions. Enzyme inactivation and standardization of sample handling can address this problem. Here a novel tissue stabilization system is used to halt degradation. After treatment samples are analyzed with downstream techniques such as western blotting or mass spectrometry.

Anatomical and neurochemical characterization of neuropeptides and proteins in striatum and n. accumbens in morphine withdrawal using Peptidomics and Imaging Mass Spectrometry.

Fred Nyberg, Uwe Rossbach, Biological Research on Drug Dependence, Per Andrén, Anna Nilsson, Maria Fälth, MMS

Repeated administration of morphine may lead to neuroadaptive changes in the brain that are thought to underlie molecular mechanisms of the development of morphine tolerance and physical dependence. Here, we employ peptidomics and MALDI imaging approaches to detect peptide and protein expression changes of the brain in rats that had developed morphine tolerance.