Publications by authors named "Riederer P"

Despite many years of research into the complex neurobiology of Parkinson's disease, the precise aetiology cannot be pinpointed down to one causative agent but rather a multitude of mechanisms. Current treatment options can alleviate symptomsbut only slightly slow down the progression and not cure the disease and its underlying causes. Factors that play a role in causing the debilitating neurodegenerative psycho-motoric symptoms include genetic alterations, oxidative stress, neuroinflammation, general inflammation, neurotoxins, iron toxicity, environmental influences, and mitochondrial dysfunction.

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Monoamine oxidase catalyzes oxidative deamination of monoamine transmitters and plays a critical role in the pathogenesis of neuropsychiatric diseases. Monoamine oxidase is classified into type A and B (MAO-A, MAO-B) according to the substrate specificity and sensitivity to inhibitors. The isoenzymes are different proteins coded by different genes localized on the X-chromosome, but they have identical intron-exon organization, similar protein structure and enzymatic mechanism and are considered to be derived from the same ancestral gene.

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Postencephalitic parkinsonism (PEP) is suggested to show a virus-induced pathology, which is different from classical idiopathic Parkinson's disease (PD) as there is no α-synuclein/Lewy body pathology. However, PEP shows a typical clinical representation of motor disturbances. In addition, compared to PD, there is no iron-induced pathology.

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Article Synopsis
  • The therapy for Parkinson's disease (PD) is personalized to target both motor and non-motor symptoms, with adjustments needed as the disease progresses and neurodegeneration occurs.
  • Monitoring dopamine substituting drugs, particularly measuring plasma levels of levodopa, is suggested to optimize treatment efficacy and manage variability in response.
  • Limited understanding of how other medications and factors like gut motility affect levodopa levels complicates treatment; further research is needed on the interactions and impacts of multiple drugs used by PD patients.
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Melanin is a crucial pigment in melanomagenesis. Its fluorescence in human tissue is exceedingly weak but can be detected through advanced laser spectroscopy techniques. The spectral profile of melanin fluorescence distinctively varies among melanocytes, nevomelanocytes, and melanoma cells, with melanoma cells exhibiting a notably "red" fluorescence spectrum.

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Fascinatingly, an abundance of recent studies has subscribed to the importance of cytotoxic immune mechanisms that appear to increase the risk/trigger for many progressive neurodegenerative disorders, including Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis, and multiple sclerosis. Events associated with the neuroinflammatory cascades, such as ageing, immunologic dysfunction, and eventually disruption of the blood-brain barrier and the "cytokine storm", appear to be orchestrated mainly through the activation of microglial cells and communication with the neurons. The inflammatory processes prompt cellular protein dyshomeostasis.

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Introduction: Establishing valid diagnostic strategies is a precondition for successful therapeutic intervention in Alzheimer's disease (AD).

Methods: One hundred forty-four healthy 75-year-old participants from the Vienna-Transdanube-Aging longitudinal cohort study were tested for neuroaxonal damage by single molecular array (Simoa) plasma neurofilament light chain (NfL) levels at baseline, 30, 60, and 90 months, and onset of AD dementia. Individual risk for sporadic AD was estimated by continuous shrinkage polygenic risk score (PRS-CS, genome-wide association study).

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Article Synopsis
  • Parkinson's disease involves the loss of dopamine neurons and the buildup of harmful proteins, particularly α-synuclein, highlighting the importance of dopamine in its pathology.
  • Beneficial treatments like L-DOPA point to dopamine deficits as a key factor, but multiple genetic and environmental elements contribute to the disease as it impacts other neurotransmitter systems as well.
  • Interactions among dopamine, α-synuclein, and certain enzymes like monoamine oxidase are crucial; compounds like rasagiline and selegiline show promise in protecting neurons by preventing harmful changes and modifying these interactions.
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Introduction: Differential expression of long non-coding RNAs (lncRNAs) is a hallmark of cardiovascular aging, cerebrovascular diseases, and neurodegenerative disorders. This research article investigates the association between a panel of lncRNAs and the risk of death and ischemic stroke in a cohort of non-institutionalized elderly subjects.

Method: A total of 361 healthy individuals aged 75 years old, prospectively recruited in the Vienna Transdanube Aging (VITA) cohort, were included.

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Dopamine was initially considered as a mere intermediate in the noradrenaline synthesis but was then found to be a neurotransmitter. Its depletion resulted in characteristic symptoms in experimental studies and could be antagonized by DOPA (3,4-dihydroxyphenylalanin), suggesting a similarity to the human disorder Parkinson´s disease (PD) and a therapeutic potential which was successfully exploited from the 1970s on. This was due to the pioneering work of Arvid Carlsson and clinicians around the world who first worked on the breakthrough of L-DOPA therapy and then on its amendment and modification and on alternative therapies for PD patients.

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Emerging studies suggest a correlation between elevated plasma homocysteine (hcy) levels and the risk of atherosclerosis, vascular disorders, and neurodegenerative diseases, including Parkinson's disease (PD). This narrative review delves into the intricate relationships between Hcy, vitamin B metabolites, dopamine-substituting compounds, and various symptoms of PD. Patients undergoing a long-term L-dopa/dopa-decarboxylase inhibitor (DDI) regimen, especially without a concurrent catechol-O-methyl transferase (COMT) inhibitor or methyl group-donating vitamin supplementation, such as vitamins B6 and B12, exhibit an elevation in Hcy and a decline in vitamin B metabolites.

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A biomarker for declined methylation capacity is elevation of homocysteine levels. They increase the risk for onset of vascular disease and contribute to progression of chronic neurodegeneration and aging. This narrative review discusses associations between homocysteine, consumption of methyl group-donating vitamins and impact on disease-generating mechanisms in levodopa-treated patients with Parkinson's disease.

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Multiple System Atrophy (MSA) and Parkinson's diseases (PD) are elite members of the α-synucleinopathy organization. Aberrant accumulations of the protein α-synuclein characterize them. A plethora of evidence indicates the involvement of these rogue inclusions in a cascade of events that disturb cellular homeostasis resulting in neuronal dysfunction.

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The heterogeneity of Parkinson's disease (PD), i.e. the various clinical phenotypes, pathological findings, genetic predispositions and probably also the various implicated pathophysiological pathways pose a major challenge for future research projects and therapeutic trail design.

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The foundation of a German Society of Biological Psychiatry (DGBP) was initiated at the Second World Congress of Biological Psychiatry of the WFSBP in Barcelona in 1978. Its mission was and is to promote interdisciplinary research on the biology of mental disorders and to translate results of biological research into clinical practice. During the presidency of Peter Falkai, its tasks were defined to improve the quality and support of biologically oriented research in Germany by the DFG (Deutsche Forschungsgemeinschaft; German Research Foundation), BMBF (Bundesministerium für Bildung und Forschung) and EU (European Union), to promote young researchers doing biologically oriented research, to improve on the diagnosis and therapy of mental disorders and to advise policy makers by taking part in legal processes.

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Since the description of some peculiar symptoms by James Parkinson in 1817, attempts have been made to define its cause or at least to enlighten the pathology of "Parkinson's disease (PD)." The vast majority of PD subtypes and most cases of sporadic PD share Lewy bodies (LBs) as a characteristic pathological hallmark. However, the processes underlying LBs generation and its causal triggers are still unknown.

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Objective: Long noncoding RNAs (lncRNAs) are involved in diabetogenesis in experimental models, yet their role in humans is unclear. We investigated whether circulating lncRNAs associate with incident type 2 diabetes in older adults.

Research Design And Methods: A preselected panel of lncRNAs was measured in serum of individuals without diabetes (n = 296) from the Vienna Transdanube Aging study, a prospective community-based cohort study.

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The dark pigment neuromelanin (NM) is abundant in cell bodies of dopamine (DA) neurons in the substantia nigra (SN) and norepinephrine (NE) neurons in the locus coeruleus (LC) in the human brain. During the progression of Parkinson's disease (PD), together with the degeneration of the respective catecholamine (CA) neurons, the NM levels in the SN and LC markedly decrease. However, questions remain among others on how NM is associated with PD and how it is synthesized.

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Article Synopsis
  • Alzheimer's disease (AD) is primarily a sporadic condition largely linked to the APOE ε4 gene, with limited disease-modifying treatments available, mainly aducanumab and lecanemab.
  • Attention-deficit hyperactivity disorder (ADHD) is common in children and persists into adulthood for many, with its treatment relying on first-line stimulants like methylphenidate (MPH) but lacking definitive disease-modifying therapies.
  • Research suggests potential links between ADHD and AD, including shared cognitive deficits and biological pathways, indicating that ADHD might increase the risk for developing AD and that treatments for ADHD might benefit cognitive function in early stages of dementia.
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Introduction: The aminoadamantanes amantadine and memantine are well known. They mainly act as N-methyl-D-aspartate antagonists.

Areas Covered: The antiviral drug amantadine moderately ameliorates impaired motor behavior in patients with Parkinson's disease.

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Neuromelanin granules (NMGs) are organelle-like structures present in the human . In addition to neuromelanin, NMGs contain proteins, lipids and metals. As NMG-containing dopaminergic neurons are preferentially lost in Parkinson's disease and dementia with Lewy bodies (DLB), it is assumed that NMGs may play a role in neurodegenerative processes.

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Neuromelanin is a black-brownish pigment, present in so-called neuromelanin granules (NMGs) in the cell bodies of dopaminergic neurons in the substantia nigra (SN) pars compacta. These neurons are lost in neurodegenerative diseases, such as Parkinson's disease and dementia with Lewy bodies. Although it is known that lipids, proteins, and environmental toxins accumulate in NMGs, the function of NMGs has not yet been finally clarified as well as their origin and the synthesis of neuromelanin.

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The clinical presentation of Parkinson's disease (PD) is both complex and heterogeneous, and its precise classification often requires an intensive work-up. The differential diagnosis, assessment of disease progression, evaluation of therapeutic responses, or identification of PD subtypes frequently remains uncertain from a clinical point of view. Various tissue- and fluid-based biomarkers are currently being investigated to improve the description of PD.

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