
Nicoletta Plotegher- PhD
- Assistant Professor at University of Padua
Nicoletta Plotegher
- PhD
- Assistant Professor at University of Padua
About
65
Publications
31,397
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Introduction
I am interested in studying how neuronal homeostasis is mantained in health and disease, and how defects in the mechanisms involved in this process impact on neuronal function and cause neurons damage. To explore these different questions, I use imaging methods, combined with biochemical and biophysical tools, in vitro, in cellular and animal models.
Current institution
Additional affiliations
Education
January 2010 - March 2013
October 2004 - October 2009
Publications
Publications (65)
When probed using fluorescence lifetime imaging microscopy (FLIM), the emission from reduced nicotinamide adenine dinucleotide (NADH) and its phosphorylated form NADPH have shown promise as sensitive intrinsic reporters of metabolism in living systems. However, an incomplete understanding of the biochemical processes controlling their fluorescence...
A β‐glucosyl sterol probe bearing a terminal alkyne moiety for fluorescent tagging enables the investigation of the neuronal and intracellular localization of this class of compounds involved in neurodegenerative diseases. The compound showed localization in the neuronal cells, with marked differences in the uptake and metabolism leading to enhance...
Alterations in the dopamine catabolic pathway are known to contribute to the degeneration of nigrostriatal neurons in Parkinson's disease (PD). The progressive cellular buildup of the highly reactive intermediate 3,4-dihydroxyphenylacetaldehye (DOPAL) generates protein cross-linking, oligomerization of the PD-linked αSynuclein (αSyn) and imbalance...
Autophagy is a highly conserved homeostatic process essential for the bulk degradation of cytoplasmic components and aggregated proteins. Multiple evidence indicates that impairment of (macro)autophagy leads to neurodegeneration, such as Parkinson disease (PD). Our previous work showed that p21 activated kinase 6 (PAK6) interacts with the PD-associ...
Background
Parkinson’s disease is a progressive neurodegenerative disorder mainly distinguished by sporadic etiology, although a genetic component is also well established. Variants in the LRRK2 gene are associated with both familiar and sporadic disease. We have previously shown that PAK6 and 14-3-3γ protein interact with and regulate the activity...
Parkinson’s disease (PD) is a multisystemic disorder that manifests through motor and non-motor symptoms. Motor dysfunction is the most debilitating and it is caused by the degeneration of dopamine-producing neurons in the substantia nigra pars compacta (SNpc). A body of evidence indicates that synapse demise precedes by years neuronal death. Still...
Parkinson’s disease (PD) is a multisystemic disorder that manifests through motor and non-motor symptoms. Motor dysfunction is the most debilitating and it is caused by the degeneration of dopamine-producing neurons in the substantia nigra pars compacta (SNpc). A body of evidence indicates that synapse demise precedes by years neuronal death. Still...
The enzyme glucocerebrosidase (GCase) catalyses the hydrolysis of glucosylceramide to glucose and ceramide within lysosomes. Homozygous or compound heterozygous mutations in the GCase-encoding GBA1 gene cause the lysosomal storage disorder Gaucher disease, while heterozygous mutations are the most frequent genetic risk factor for Parkinson's diseas...
Parkinson’s disease (PD) is a progressive neurodegenerative disorder mainly distinguished by sporadic aetiology, although a genetic component is also well established. Variants in the LRRK2 gene are associated with both familiar and sporadic forms of the disease. We have previously shown that PAK6 and 14-3-3γ interact with and regulate the activity...
Oxygen reactive species (ROS) are a group of molecules generated from the incomplete reduction of oxygen. Due to their high reactivity, ROS can interact with and influence the function of multiple targets, which include DNA, lipids, and proteins. Among the proteins affected by ROS, AMP-activated protein kinase (AMPK) is considered a major sensor of...
Sex hormones and genes on the sex chromosomes are not only key factors in the regulation of sexual differentiation and reproduction but they are also deeply involved in brain homeostasis. Their action is crucial for the development of the brain, which presents different characteristics depending on the sex of individuals. The role of these players...
Background: Parkinson's disease is a progressive neurodegenerative disorder mainly distinguished by sporadic aetiology, although a genetic component is also well established. Variants in the LRRK2 gene are associated with both familiar and sporadic disease. We have previously shown that PAK6 and 14-3-3gamma protein interact with and regulate the ac...
Dopamine dyshomeostasis has been acknowledged among the determinants of nigrostriatal neuron degeneration in Parkinson’s disease (PD). Several studies in experimental models and postmortem PD patients underlined increasing levels of the dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL), which is highly reactive towards proteins. DOPAL has...
The protein DJ-1 is mutated in rare familial forms of recessive Parkinson's disease and in parkinsonism accompanied by amyotrophic lateral sclerosis symptoms and dementia. DJ-1 is considered a multitasking protein able to confer protection under various conditions of stress. However, the precise cellular function still remains elusive. In the prese...
Mitochondria, endoplasmic reticulum and lysosomes are involved in different pathways that can regulate pre-synaptic function. In particular, they could modulate ATP availability in response to rapid changes, could control synaptic protein levels and adjust Ca2+ signalling, which could all impact on neuronal activity. Organelles functions in these p...
Parkinson’s disease (PD) is a multisystemic disorder that manifests through motor and non-motor symptoms. Motor dysfunction is the most debilitating and it is caused by the degeneration of dopamine-producing neurons in the substantia nigra pars compacta (SNpc). A body of evidence indicates that synapse demise precedes by years neuronal death. Still...
The Excitatory Amino Acid Transporter 2 (EAAT2) accounts for 80% of brain glutamate clearance and is mainly expressed in astrocytic perisynaptic processes. EAAT2 function is finely regulated by endocytic events, recycling to the plasma membrane and degradation. Noteworthy, deficits in EAAT2 have been associated with neuronal excitotoxicity and neur...
Leucine-rich repeat kinase 2 (LRRK2) is a kinase involved in different cellular functions, including autophagy, endolysosomal pathways, and immune function. Mutations in LRRK2 cause autosomal-dominant forms of Parkinson’s disease (PD). Heterozygous mutations in GBA1, the gene encoding the lysosomal enzyme glucocerebrosidase (GCase), are the most co...
The microphthalmia/transcription factor E (MiTF/TFE) transcription factors are responsible for the regulation of various key processes for the maintenance of brain function, including autophagy-lysosomal pathway, lipid catabolism, and mitochondrial homeostasis. Among them, autophagy is one of the most relevant pathways in this frame; it is evolutio...
The Excitatory Amino Acid Transporter 2 (EAAT2) accounts for 80% of brain glutamate clearance and is mainly expressed in astrocytic perisynaptic processes. EAAT2 function is finely regulated by endocytic events, recycling to the plasma membrane and degradation. Noteworthy, deficits in EAAT2 have been associated with neuronal excitotoxicity and neur...
LRRK2 is a kinase involved in different cellular functions, including autophagy, endolysosomal pathways and vesicle trafficking. Mutations in LRRK2 cause autosomal dominant forms of Parkinson's disease (PD). Heterozygous mutations in GBA1, the gene encoding the lysosomal enzyme glucocerebrosidase (GCase), are the most common genetic risk factors fo...
The Excitatory Amino Acid Transporter 2 (EAAT2) accounts for 80% of brain glutamate clearance and is mainly expressed in astrocytic perisynaptic processes. EAAT2 function is finely regulated by endocytic events, recycling to the plasma membrane and degradation. Noteworthy, deficits in EAAT2 have been associated with neuronal excitotoxicity and neur...
Parkinson’s disease (PD) is a neurodegenerative, progressive disease without a cure. To prevent PD onset or at least limit neurodegeneration, a better understanding of the underlying cellular and molecular disease mechanisms is crucial. Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene represent one of the most common causes of familial PD...
Dopamine dyshomeostasis has been acknowledged to be among the determinants of nigrostriatal neuron degeneration in Parkinson's disease (PD). Several studies in experimental models and postmortem PD patients underlined increasing levels of the aldehydic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL), which is highly reactive towards pro...
Parkinson’s disease (PD) is a proteinopathy associated with the aggregation of α-synuclein and the formation of lipid–protein cellular inclusions, named Lewy bodies (LBs). LB formation results in impaired neurotransmitter release and uptake, which involve membrane traffic and require lipid synthesis and metabolism. Lipids, particularly ceramides, a...
Excitotoxicity is likely to occur in pathological scenarios in which mitochondrial function is already compromised, shaping neuronal responses to glutamate. In fact, mitochondria sustain cell bioenergetics, tune intracellular Ca²⁺ dynamics, and regulate glutamate availability by using it as metabolic substrate. Here, we suggest the need to explore...
Proteins reconfigure their 3D‐structure, and consequently their function, under the control of specific molecular interactions that sense, process and transmit information from the surrounding environment. When this fundamental process is hampered, many pathologies occur as in the case of protein misfolding diseases. In this work, we follow the ear...
A photo‐responsive prion‐like foldamer is designed to act as spatio‐temporal molecular template, which can be activated by selective photo‐irradiation without changing other experimental conditions. It is able to induce a fast transition to the β‐sheet conformation for aS monomers that undergo fibrillar polymerization. This method allows the study...
Mutations in LRRK2 cause familial Parkinson’s disease and common variants increase disease risk. LRRK2 kinase activity and cellular localization are tightly regulated by phosphorylation of key residues, primarily Ser1292 and Ser935, which impacts downstream phosphorylation of its substrates, among which Rab10. A comprehensive characterization of LR...
Background
Parkinson’s disease (PD) is a neurodegenerative, progressive disease without cure. To prevent PD onset or at least limit neurodegeneration, a better understanding of the underlying cellular and molecular disease mechanisms is crucial. Mutations in the leucine rich repeat kinase 2 ( LRRK2 ) gene represent one of the most common causes of...
In-solution synchrotron Small-angle X-ray Scattering (SAXS) technique has been used to investigate an Intrinsically Disordered Protein (IDP) related to Parkinson’s disease, the α-synuclein (α-syn), in pre-fibrillar diluted conditions. SAXS experiments have been performed as a function of temperature and concentration on the Wild-Type (WT) and on th...
Mutations of the mitochondrial genome (mtDNA) cause a range of profoundly debilitating clinical conditions for which treatment options are very limited. Most mtDNA diseases show heteroplasmy - tissues express both wild-type and mutant mtDNA. While the level of heteroplasmy broadly correlates with disease severity, the relationships between specific...
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Heterozygous mutations of the lysosomal enzyme glucocerebrosidase (GBA1) represent the major genetic risk for Parkinson’s disease (PD), while homozygous GBA1 mutations cause Gaucher disease, a lysosomal storage disorder, which may involve severe neurodegeneration. We have previously demonstrated impaired autophagy and proteasomal degradation pathwa...
The preferential loss of dopaminergic neurons in the substantia nigra pars compacta is one of the pathological hallmarks characterizing Parkinson’s disease. Although the pathogenesis of this disorder is not fully understood, oxidative stress plays a central role in the onset and/or progression of Parkinson’s disease and dopamine itself has been sug...
A full understanding of Parkinson’s Disease etiopathogenesis and of the causes of the preferential vulnerability of nigrostriatal dopaminergic neurons is still an unsolved puzzle. A multiple-hit hypothesis has been proposed, which may explain the convergence of familial, environmental and idiopathic forms of the disease. Among the various determina...
Ceramides (Cer) constitute a class of lipids present in the cell membranes where they act as structural components, but they can also work as signaling molecules. Increasing genetic and biochemical evidence supports a link between deregulation of ceramide metabolism in the brain and neurodegeneration. Here, we provide an overview of the genes and c...
Parkinson's disease (PD) is the most common motor neurodegenerative disorder. In most cases the cause of the disease is unknown, while in about 10% of subjects, it is associated with mutations in a number of different genes. Several different mutations in 15 genes have been identified as causing familial forms of the disease, while many others have...
The analysis of the α-synuclein (aS) aggregation process, which is involved in Parkinson's disease etiopathogenesis, and of the structural feature of the resulting amyloid fibrils may shed light on the relationship between the structure of aS aggregates and their toxicity. This may be considered a paradigm of the ground work needed to tackle the mo...
α–synuclein amyloid fibrils are found in surviving neurons of Parkinson's disease affected patients, but the role they play in the disease development is still under debate. A growing number of evidences points to soluble oligomers as the major cytotoxic species, while insoluble fibrillar aggregates could even play a protection role. In this work,...
Lysosomal storage disorders (LSDs) are rare inherited debilitating and often fatal disorders. Caused by mutations affecting lysosomal proteins, LSDs are characterized by the accumulation of undegraded material in lysosomes and by lysosomal dysfunction. Although LSDs are multisystemic diseases, the majority display neurologic symptoms and neurodegen...
Parkinson’s disease is a neurodegenerative disorder characterized by the death of dopaminergic neurons and by accumulation of alpha-synuclein (aS) aggregates in the surviving neurons. The dopamine catabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL) is a highly reactive and toxic molecule that leads to aS oligomerization by covalent modifications to...
Mutations in LRRK2 gene cause inherited Parkinson's disease (PD) and variations around LRRK2 act as risk factor for disease. Similar to sporadic disease, LRRK2-linked cases show late onset and, typically, the presence of proteinaceous inclusions named Lewy bodies (LBs) in neurons. Recently, defects on ceramide (Cer) metabolism have been recognized...
Background
Lrrk2, a gene linked to Parkinson’s disease, encodes a large scaffolding protein with kinase and GTPase activities implicated in vesicle and cytoskeletal-related processes. At the presynaptic site, LRRK2 associates with synaptic vesicles through interaction with a panel of presynaptic proteins.
Results
Here, we show that LRRK2 kinase a...
Background
Over-activated microglia and chronic neuroinflammation contribute to dopaminergic neuron degeneration and progression of Parkinson’s disease (PD). Leucine-rich repeat kinase 2 (LRRK2), a kinase mutated in autosomal dominantly inherited and sporadic PD cases, is highly expressed in immune cells, in which it regulates inflammation through...
Background
Over-activated microglia and chronic neuroinflammation contribute to dopaminergic neuron degeneration and progression of Parkinson’s disease (PD). Leucine-rich repeat kinase 2 (LRRK2), a kinase mutated in autosomal dominantly inherited and sporadic PD cases, is highly expressed in immune cells, in which it regulates inflammation through...
α-Synuclein (aS) aggregation has been amply investigated for its involvement in Parkinson's disease because its amyloid fibrils are the main constituent of Lewy bodies, one of the hallmarks of the disease. aS aggregation was studied here in vitro and in cellular models to correlate aggregation products with toxicity mechanisms. Independent results...
Familial and idiopathic Parkinson's disease (PD) is associated with the abnormal neuronal accumulation of α-synuclein (aS) leading to β-sheet-rich aggregates called Lewy Bodies (LBs). Moreover, single point mutation in aS gene and gene multiplication lead to autosomal dominant forms of PD. A connection between PD and the 14-3-3 chaperone-like prote...
a-Synuclein (aS) aggregation has been
amply investigated for its involvement in Parkinson’s disease
because its amyloid fibrils are the main constituent of
Lewy bodies, one of the hallmarks of the disease. aS aggregationwas
studied here in vitro and in cellularmodels to
correlate aggregation products with toxicity mechanisms.
Independent results pu...
Alpha-synuclein (aS) and its aggregation properties are central in the development and spread of Parkinson's disease. Point mutations and multiplications of the SNCA gene encoding aS cause autosomal dominant forms of the disorder. Moreover, protein inclusions found in the surviving neurons of parkinsonian brains consist mainly of a fibrillar form o...
Parkinson's disease (PD) is one of the most common neurodegenerative diseases. It is characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta of the brain. Another feature is represented by the formation in these cells of inclusions called Lewy bodies (LB), principally constituted by fibrillar α-synuclein (αSyn). This...
Comment on
"Disrupted autophagy leads to dopaminergic axon and dendrite degeneration and promotes presynaptic accumulation of α-synuclein and LRRK2 in the brain. [J Neurosci. 2012]"
Alpha-synuclein is a natively unfolded protein widely expressed in neurons at the presynaptic level. It is linked to Parkinson's disease by two lines of evidence: amyloid fibrils of the protein accumulate in patients' brains and three genetic mutants cause autosomal dominant forms of the disease. The biological role of the protein and the mechanism...
We show via single-molecule mechanical unfolding experiments that the osmolyte glycerol stabilizes the native state of the human cardiac I27 titin module against unfolding without shifting its unfolding transition state on the mechanical reaction coordinate. Taken together with similar findings on the immunoglobulin-binding domain of streptococcal...
Questions
Questions (6)
DOPAL is cathecolaldehyde resulting from dopamine metabolism, involved in Parkinson's disease ethiopathogenesis. ALR is one of the enzyme responsible for its detoxification, but we could not find information about the DOPAL affinity for it.
Glucocerebrosidase (GCase) is a lysosomal enzyme (EC 3.2.1.45) encoded by GBA gene and responsible for the hydrolysis of glucosylceramides, an intermediate in glycolipid metabolism. The resulting products are glucose and ceramide molecules.
I can't find any report about the inhibition of its enzymatic activity by iits products (i.e. by ceramides). Do you know more?
I performed activity assays on cell lysates following the protocol described in Osellame et al. 2013.
I purchased 4-Methylumbelliferyl β-D-glucopyranoside from Sigma (M3633) and in the datasheed it is described as soluble in N,N-dimethylformamide
(DMF, 50 mg/ml), but for enzyme assays, it suggests to dissolve it at
5 mM (1.7 mg/ml) in water or 0.2 M sodium citratephosphate
buffer. I tried the second option and I couldn't get a fully solubilized solution (some white particles were still present in suspension in the buffer) which affected the compound concentration.
Any idea about why I am getting this problem and how to solve it? I have to say that this problem occurs randomly and is not associated to a specific batch of 4-Methylumbelliferyl β-D-glucopyranoside or buffer I am using.
Thanks for any help.
Please provide references to papers in which alpha-synuclein concentration is estimated or to papers in which a suitable method to quantify protein concentration in neurons is applied.
It would be great to have also a reference where I can read something more about this issue.