Publications by authors named "Alexandra Zinnen"
Article Synopsis
- Cardiac pressure overload can lead to problems for patients with congenital heart defects, and using stem cell-derived heart cells might help improve heart function alongside surgery.
- Researchers successfully implanted human stem cell-derived heart cells into the hearts of rhesus macaques facing induced pressure overload, achieving good integration with the existing heart tissue.
- Although some monkeys experienced episodes of ventricular tachycardia after the cell transplant, these events generally resolved within a few weeks, indicating a need for monitoring but also promising potential for this treatment approach.
Objective: The objective of this study was to develop and evaluate the feasibility and safety of a novel transaxial surgical approach for the delivery of human induced pluripotent stem cell-derived dopaminergic neuroprogenitor cells (DANPCs) into the putamen nucleus using nonhuman primates and surgical techniques and tools relevant to human clinical translation.
Methods: Nine immunosuppressed, unlesioned adult cynomolgus macaques (4 females, 5 males) received intraputaminal injections of vehicle or DANPCs (0.9 × 105 to 1.
α-Synuclein (α-syn) proteinopathy in the neurons of the Enteric Nervous System (ENS) is proposed to have a critical role in Parkinson's disease (PD) onset and progression. Interestingly, the ENS of the human appendix harbors abundant α-syn and appendectomy has been linked to a decreased risk and delayed onset of PD, suggesting that the appendix may influence PD pathology. Common marmosets and rhesus macaques lack a distinct appendix (a narrow closed-end appendage with a distinct change in diameter at the junction with the cecum), yet the cecal microanatomy of these monkeys is similar to the human appendix.
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- The study investigates how gastrointestinal inflammation from food-borne pathogens might trigger Parkinson's disease by examining α-synuclein buildup in nonhuman primates.
- Adult female macaques were exposed to a common pathogen to see if acute GI inflammation caused persistent pathological changes related to PD.
- Results showed minimal clinical signs of infection or significant α-synuclein changes, suggesting that other factors might influence the relationship between food-borne pathogens and Parkinson's disease.
Minimal myelination is proposed to be a contributing factor to the preferential nigral neuronal loss in Parkinson's disease (PD). Similar to nigral dopaminergic neurons, sympathetic neurons innervating the heart have long, thin axons which are unmyelinated or minimally myelinated. Interestingly, cardiac sympathetic loss in PD is heterogeneous across the heart, yet the spatial relationship between myelination and neurodegeneration is unknown.
View Article and Find Full Text PDFCardiac dysautonomia is a common nonmotor symptom of Parkinson's disease (PD) associated with loss of sympathetic innervation to the heart and decreased plasma catecholamines. Disease-modifying strategies for PD cardiac neurodegeneration are not available, and biomarkers of target engagement are lacking. Systemic administration of the catecholaminergic neurotoxin 6-hydroxydopamine (6-OHDA) recapitulates PD cardiac dysautonomia pathology.
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