DIFFERENTIATION-INDUCED CHANGES IN ANTIOXIDANT CAPACITY AND ANTIOXIDANT RESPONSE IN SH-SY5Y CELLS: ROLE OF NRF2

Organisms are exposed to reactive oxygen species from internal metabolism and environmental toxicant exposure, which have been linked to the initiation and progression of many neuronal diseases such as Alzheimer’s and Parkinson’s diseases. Exposure to reactive oxygen species are counterbalanced by antioxidant defense systems such as the Nrf2-ARE pathway, the primary regulator of endogenous antioxidant response. Whereas neuronal cells are post-mitotic and are particularly susceptible to oxidative stress because of high oxygen consumption, astrocytes are mitotic and rely more on glycolytic metabolism. In this study, the difference in antioxidant response and capacity in mitotic and post-mitotic cells were investigated using undifferentiated and differentiated SH-SY5Y neuroblastoma cells. The investigations of this study focused on the induction of antioxidant enzymes in SH-SY5Y cells by Nrf2 using tert-Butylhydroquinone (tBHQ). The levels of GSH, Mn-SOD, HO and OGG1 which are all induced by Nrf2 were determined. The results of the experiment showed that differentiated (post-mitotic) and undifferentiated (mitotic) cells responded similarly to Nrf2 induction as was observed in the higher levels of GSH, HO, Mn-SOD and OGG1 compared to the control group. As compared to undifferentiated cells, differentiated cells had relatively lower antioxidant levels except in the case of Mn-SOD. This suggests that post-mitotic and mitotic cells respond to antioxidant induction similarly but differ in their antioxidant capacities. The study also compared DTNB and HPLC methods in determining GSH levels in these cells. The outcome of the experiments showed that HPLC offers a selective method in determining GSH levels

Alpha Synuclein-spezifische T Lymphocytes verursachen Neurodegeneration im A53T-α-synuclein Parkinson-Krankheitsmodell

Parkinson’s disease (PD), which is the most common motor neurodegenerative disorder has attracted a tremendous amount of research advancement amid the challenges of the lack of an appropriate model that summate all the features of the human disease. Nevertheless, an aspect of the disease that is yet to be fully elucidated is the role of the immune system particularly the adaptive arm in the pathogenesis of PD. The focus of this study therefore was to characterize the contribution of lymphocytes in PD using the AAV1/2-A53T-α-synuclein mouse model of the disease that encodes for human mutated A53T-α-synuclein. This model was suitable for this research because it reflects more faithfully the molecular pathology underlying the human disease by exhibition of insoluble α-synuclein containing Lewy-like protein aggregates as compared to the more classical toxin models used in PD research. The outcome of this study showed that stereotaxic delivery of pathogenic α-synuclein via a viral vector into the substantia nigra engender the invasion of activated CD4+ and CD8+ T lymphocytes in the brain. The invasion of activated T cells in the brain especially in the substantia nigra then results in enhanced microglial activation and the disintegration of dopaminergic neurons. In addition, it was also discovered that CD4+ T cells augmented dopaminergic cell death to a greater extent than CD8+ T cells although; axonal degeneration occurred relatively independent from T cells contribution. The ex vivo and in vitro, experiments also indicated that the T cells were not only activated but they were specific to the mutated human α-synuclein antigen. As a result, they demonstrated selectivity in inducing more cell death to primary hippocampal neurons transduced with AAV1/2-A53T-α-synuclein vector than neurons with empty viral vector infection. The mechanism of T cell induced neuronal cell loss could not be attributed to the presence of cytokines neither was it mediated through MHC I and II. On the whole, this research has established that the presence of pathogenic α-synuclein in the substantia nigra has the potential to trigger immune responses that involve the transmigration of adaptive immune cells into the brain. The infiltration of the T cells consequently has a detrimental effect on the survival of dopaminergic neurons and the progression of the diseaseDer M. Parkinson (PD) ist die am häufigsten auftretende motorische neurodegenerative Erkrankung weltweit. Trotz des Fehlens eines geeigneten Tiermodells, das alle Merkmale der menschlichen Krankheit widerspiegelt, kann die Parkinsonforschung in letzter Zeit einen enormen Fortschritt verzeichnen. Dennoch ist ein Aspekt der Krankheit, der noch nicht vollständig geklärt wurde, die Rolle von Immunzellen, insbesondere des adaptiven Arms in der Pathogenese der PD. Der Fokus dieser Studie lag daher auf der Charakterisierung des Beitrags von T-Zellen in der PD unter Verwendung des humanen mutierten AAV1/2-A53T-α- Synuclein-Mausmodells der Parkinsonkrankheit. Dieses Modell war für die vorliegende Arbeit optimal geeignet, da es die molekulare Pathologie der menschlichen Krankheit im Gegensatz zu den klassischen Toxinmodellen in der PD-Forschung besser widerspiegelt. Das Ergebnis dieser Studie zeigte, dass die stereotaktische Injektion von pathogenem α-synuclein über einen viralen Vektor in die Substantia nigra die Infiltration aktivierter CD4+ - und CD8+ T-Lymphozyten im Gehirn hervorruft. Die Einwanderung aktivierter T-Zellen im Gehirn, insbesondere in der Substantia nigra, führte begleitet durch eine verstärkte Mikroglia- Aktivierung zum Verlust dopaminerger Neurone. Darüber hinaus wurde beobachtet, dass CD4+ T-Zellen den Untergang von dopaminergen Neuronen in einem größeren Ausmaß als CD8+ T-Zellen verursachten. Interessanterweise trat die axonale Degeneration dopaminerger Fasern im Striatum relativ unabhängig von den T-Zellen auf. Durch ex vivo und in vitro Experimente konnte nachgewiesen werden, dass die T-Zellen nicht nur aktiviert waren, sondern auch antigenspezifisch gegen das mutierte humane α-Synuclein-Antigen reagierten. Als Ergebnis zeigten sie Selektivität bei der Herbeiführung eines höheren Zelltods für Dabei zeigten AAV1/2-A53T-α-Synuclein-Vektor transduzierte primäre Hippocampus-Neurone einen verstärkten Zelltod durch Inkubation mit T-Zellen aus dem Gehirn von AAV1/2-A53T- α-Synuclein-Vektor injizierten Mäusen als Neurone nach Injektion mit leerem AAV. Der Mechanismus des durch T-Zellen induzierten neuronalen Zellverlusts konnte nicht auf das Vorhandensein von Zytokinen zurückgeführt werden. Insgesamt konnte diese Arbeit zeigen, dass das Vorhandensein von pathogenem α-synuclein in der Substantia nigra in dem AAV1/2- A53T-α-synuclein Mausmodell des PD das Potenzial hat, Immunreaktionen auszulösen, welche die Transmigration adaptiver Immunzellen in das Gehirn und einen konsekutiven Verlust dopaminerger Neurone verursachen

When Contraceptive Means No Pregnancy: Narrative Account of Contraceptive Use among Reproductive Women at the Tamale Teaching Hospital, Ghana

Contraception is a major intervention in improving maternal health. There are about 214 million women of reproductive age in developing countries who are not using modern contraception to prevent pregnancy. For proper locale-specific analysis of female reproductive health issues in Ghana, it is vital to explore the knowledge base and hindrances to contraception use in local communities. We used a phenomenological design to study reproductive- aged women in the Tamale Metropolis of the Northern Region of Ghana in order to comprehend the life world of study participants. This research demonstrates that the majority of the women in the study area have some form of knowledge about contraception, with mass media being their main source of information. The contraception methods known and cited by participants included birth control pills, condoms, injectable methods, and IUDs, with the prevention of unwanted pregnancies as the main reason for using contraceptives. For most of the participants, side effects and spiritual beliefs are the major hindrances to the use of contraception. We recommend that information on reproductive health in the Tamale Metropolis should not be limited to health facilities but should include the use of media outlets and social media platforms. Finally, clinicians should actively educate religious leaders in the metropolis to demystify the numerous superstitious beliefs associated with the use of contraception in the area