Browsing by Subject "Parkinson disease"

Now showing 1 - 2 of 2
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    Bidirectional gut-to-brain and brain-to-gut propagation of synucleinopathy in non-human primates
    (Oxford University Press, 2020-05-07) Herrero Ezquerro, María Trinidad; Arotcarena, Marie-Laure; Dovero, Sandra; Prigent, Alice; Bourdenx, Mathieu; Camus, Sandrine; Porras, Gregory; Thiolat, Marie-Laure; Tasselli, Maddalena; Aubert, Philippe; Kruse, Niels; Mollenhauer, Brit; Trigo Damas, Ines; Estrada, Cristina; Garcia-Carrillo, Nuria; Vaikath, Nishant; El-Agnaf, Omar M.A.; Vila, Miquel; Obeso, Jose A.; Derkinderen, Pascal; Dehay, Benjamin; Bezard, Erwan; Anatomía Humana y Psicobiología
    In Parkinson’s disease, synucleinopathy is hypothesized to spread from the enteric nervous system, via the vagus nerve, to the CNS. Here, we compare, in baboon monkeys, the pathological consequences of either intrastriatal or enteric injection of a-synucleincontaining Lewy body extracts from patients with Parkinson’s disease. This study shows that patient-derived a-synuclein aggregates are able to induce nigrostriatal lesions and enteric nervous system pathology after either enteric or striatal injection in a non-human primate model. This finding suggests that the progression of a-synuclein pathology might be either caudo-rostral or rostro-caudal, varying between patients and disease subtypes. In addition, we report that a-synuclein pathological lesions were not found in the vagal nerve in our experimental setting. This study does not support the hypothesis of a transmission of a-synuclein pathology through the vagus nerve and the dorsal motor nucleus of the vagus. Instead, our results suggest a possible systemic mechanism in which the general circulation would act as a route for long-distance bidirectional transmission of endogenous a-synuclein between the enteric and the central nervous systems. Taken together, our study provides invaluable primate data exploring the role of the gut-brain axis in the initiation and propagation of Parkinson’s disease pathology and should open the door to the development and testing of new therapeutic approaches aimed at interfering with the development of sporadic Parkinson’s disease.
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    Melanopsin-expressing retinal ganglion cells in aging and disease.
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2019) Esquiva, Gema; Hannibal, Jens
    Melanopsin-expressing retinal ganglion cells (mRGCs) constitute a system in the mammalian retina used for irradiance detection, regulating non-image forming functions, such as photoentrainment of circadian rhythms, control of the pupillary light reflex, masking response, light-regulated melatonin secretion, and modulation of the sleep/wake cycle. There are five subtypes of mRGCs differentiated by morphology and function. Recent years of research on mRGCs have identified a broad number of neurodegenerative diseases in the eye and the brain with altered physiologic light responses, leading to disturbances of non-image forming light response(s). In this review, we briefly summarise the melanopsin system in the normal retina and discuss its role in connection to human aging (sleep/wake problems) and retinal pathology in Alzheimer and Parkinson diseases, diabetic retinopathy, mitochondrial optic neuropathies, glaucoma, retinitis pigmentosa, and in photophobia during migraine and in seasonal affective disorder (SAD). Finally, we discuss the diagnostic tools that are being used to differentiate retinal diseases involving the melanopsin system in the rods and cones from the inner versus the outer retina.