Mutations in the gene, which encodes the abundant brain G-protein G , result in neurologic disorders characterized by developmental delay, epilepsy, and movement abnormalities. There are over 50 mutant alleles associated with disorders; the R209H mutation results in dystonia, choreoathetosis, and developmental delay without seizures. Mice heterozygous for the human mutant allele ( ) exhibit hyperactivity in open field tests but no seizures.
View Article and Find Full Text PDFBackground: Parkinson's disease (PD) is a neurodegenerative disorder that is characterized by the presence of proteinaceous alpha-synuclein (α-syn) inclusions (Lewy bodies), markers of neuroinflammation and the progressive loss of nigrostriatal dopamine (DA) neurons. These pathological features can be recapitulated in vivo using the α-syn preformed fibril (PFF) model of synucleinopathy. We have previously determined that microglia proximal to PFF-induced nigral α-syn inclusions increase in soma size, upregulate major-histocompatibility complex-II (MHC-II) expression, and increase expression of a suite of inflammation-associated transcripts.
View Article and Find Full Text PDFParkinson's disease (PD) is characterized by the accumulation of misfolded alpha-synuclein (α-syn) protein, forming intraneuronal Lewy body (LB) inclusions. The α-syn preformed fibril (PFF) model of PD recapitulates α-syn aggregation, progressive nigrostriatal degeneration and motor dysfunction; however, little is known about the time course of PFF-induced alterations in basal and evoked dopamine (DA). In vivo microdialysis is well suited for identifying small changes in neurotransmitter levels over extended periods.
View Article and Find Full Text PDFParkinson's disease (PD) pathology is characterized by alpha-synuclein (α-syn) aggregates, degeneration of dopamine neurons in the substantia nigra pars compacta (SNpc), and neuroinflammation. The presence of reactive glia correlates with deposition of pathological α-syn in early-stage PD. Thus, understanding the neuroinflammatory response of microglia and astrocytes to synucleinopathy may identify therapeutic targets.
View Article and Find Full Text PDFNeuroinflammation has become a well-accepted pathologic hallmark of Parkinson's disease (PD). However, it remains unclear whether inflammation, triggered by α-syn aggregation and/or degeneration, contributes to the progression of the disease. Studies examining neuroinflammation in PD are unable to distinguish between Lewy body-associated inflammation and degeneration-associated inflammation, as both pathologies are present simultaneously.
View Article and Find Full Text PDFβ2-adrenoreceptor (β2AR) agonists have been associated with a decreased risk of developing Parkinson's disease (PD) and are hypothesized to decrease expression of both alpha-synuclein mRNA (Snca) and protein (α-syn). Effects of β2AR agonist clenbuterol on the levels of Snca mRNA and α-syn protein were evaluated in vivo (rats and mice) and in rat primary cortical neurons by two independent laboratories. A modest decrease in Snca mRNA in the substantia nigra was observed after a single acute dose of clenbuterol in rats, however, this decrease was not maintained after multiple doses.
View Article and Find Full Text PDFBackground: Positron emission tomography (PET) imaging in early Parkinson's disease (PD) subjects reveals that increased dopamine (DA) turnover and reduced dopamine transporter (DAT) density precede decreases in DA synthesis and storage. The rat α-synuclein preformed fibril (α-syn PFF) model provides a platform to investigate DA dynamics during multiple stages of α-syn inclusion-triggered nigrostriatal degeneration.
Objectives: We investigated multiple aspects of in vivo dopaminergic deficits longitudinally and similarities to human PD using translational PET imaging readouts.
Front Endocrinol (Lausanne)
December 2021
Cytochrome P450s (CYPs) are an essential family of enzymes in the human body. They play a crucial role in metabolism, especially in human steroid biosynthesis. Reactions catalyzed by these enzymes are highly stereo- and regio-specific.
View Article and Find Full Text PDFPreclinical studies show a link between subthalamic nucleus (STN) deep brain stimulation (DBS) and neuroprotection of nigrostriatal dopamine (DA) neurons, potentially through brain-derived neurotrophic factor (BDNF) signaling. However, the question of whether DBS of the STN can be disease-modifying in Parkinson's disease (PD) remains unanswered. In particular, the impact of STN DBS on α-synuclein (α-syn) aggregation, inclusion-associated neuroinflammation, and BDNF levels has yet to be examined in the context of synucleinopathy.
View Article and Find Full Text PDFAnabolic androgenic steroids (AAS) are prohibited as doping substances in sports by the World Anti-Doping Agency. Concentrations and concentration ratios of endogenous AAS (steroid profile markers) in urine samples collected from athletes are used to detect their administration. Certain (non-prohibited) drugs have been shown to influence the steroid profile and thereby sophisticate anti-doping analysis.
View Article and Find Full Text PDFAnabolic androgenic steroids (AAS) are prohibited as performance-enhancing drugs in sports. Among them, testosterone and its precursors are often referred to as "pseudoendogenous" AAS, that is, endogenous steroids that are prohibited when administered exogenously. To detect their misuse, among other methods, the World Anti-Doping Agency-accredited laboratories monitor the steroid profile (concentrations and concentration ratios of endogenous steroids, precursors and metabolites) in urine samples collected from athletes in and out of competition.
View Article and Find Full Text PDFJ Steroid Biochem Mol Biol
November 2019
Cytochrome P450 enzymes (CYPs) are capable of catalyzing regio- and stereo-specific oxy functionalization reactions, which otherwise are major challenges in organic chemistry. In order to make the best possible use of these biocatalysts it is imperative to understand their specificities. Human CYP21A2 (steroid 21-hydroxylase) acts on the side-chain attached to C-17 in ring D of a steroid substrate, but the configuration of ring A also plays a prominent role in substrate cognition.
View Article and Find Full Text PDFAnimal models have significantly advanced our understanding of Parkinson's disease (PD). Alpha-synuclein (α-syn) has taken center stage due to its genetic connection to familial PD and localization to Lewy bodies, one pathological hallmark of PD. Animal models developed on the premise of elevated alpha-synuclein via germline manipulation or viral vector-mediated overexpression are used to investigate PD pathophysiology and vet novel therapeutics.
View Article and Find Full Text PDFAnabolic androgenic steroids (AAS) are misused very frequently in sport competitions as performance enhancing agents. One of the doping compounds that has been detected with increased frequency in the last few years is dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy-17α-methylandrosta-1,4-dien-3-one; brand name Oral Turinabol). The long-term DHCMT metabolite 20βOH-NorDHCMT (4-chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-1,4,13-trien-3-one) was reported earlier to be detectable in urine samples for more than 22 days after DHCMT administration; however, purified reference material was not available so far.
View Article and Find Full Text PDFFowlpox (FP)-vectored avian influenza (FP-AI) vaccines are used in 1-day-old chickens, but they have also recently been shown to be immunogenic in ducks. The objectives of this work were 1) to evaluate safety and to compare the immunogenicity in ducks of three poxvirus vectors (fowlpox, canarypox, and vaccinia) expressing the same hemagglutinin gene from an H5N1 isolate, 2) to study the effect of the dose of the FP-AI and the presence of an adjuvant in 1-day-old Pekin ducks on antibody response after a boost with inactivated vaccine given 3 wk later, and 3) to confirm the immunogenicity of such a heterologous prime-boost vaccination scheme in 1-day-old Muscovy ducks. Immunogenicity induced by the three poxvirus vectors was comparable, and the FP vector was selected for the other studies.
View Article and Find Full Text PDF