• COVID-19 and Parkinson’s disease: shared inflammatory pathways under oxidative stress

      Chaudhry, Zahara Latif; Klenja, Donika; Janjua, Najma; Cami-Kobeci, Gerta; Ahmed, Bushra Y.; University of Bedfordshire; University of Bristol; Kawasaki Medical School (MDPI, 2020-10-31)
      The current coronavirus pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in a serious global health crisis. It is a major concern for individuals living with chronic disorders such as Parkinson’s disease (PD). Increasing evidence suggests an involvement of oxidative stress and contribution of NFκB in the development of both COVID-19 and PD. Though, it is early to identify if SARS-CoV-2 led infection enhances PD complications, it is likely that oxidative stress may exacerbate PD progression in COVID-19 affected individuals and/or vice versa. In the current study, we sought to investigate whether NFκB-associated inflammatory pathways following oxidative stress in SARS-CoV-2 and PD patients are correlated. Toward this goal, we have integrated bioinformatics analysis obtained from BLASTP search for similarities between SARS-CoV-2 proteins and human proteome, literature review, and laboratory data obtained in a human cell model of PD. A Parkinson’s like state was created in 6OHDA-induced differentiated dopaminergic neurons (dDCNs) obtained from ReNVM cell line. The results indicated that SARS-CoV-2 infection and 6OHDA-induced toxicity triggered stimulation of caspases -2, -3 and -8 via the NFκB pathway resulting in death of dDCNs. Furthermore, specific inhibitors for NFκB and studied caspases reduced the death of stressed dDCNs. The findings suggest that knowledge of the selective inhibition of caspases and NFκB activation may contribute to development of potential therapeutic approaches for the treatment of COVID-19 and PD.
    • A novel human neuronal cell model to study iron accumulation in Parkinson’s disease

      Mehta, Kosha; Ahmed, Bushra Y.; Farnaud, Sébastien; University of Bedfordshire (OMICS International, 2019-02-11)
      Objectives: With an estimated seven to ten million sufferers worldwide, Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder. Progress in elucidating its causes has been slow, partly due to the lack of human-relevant models. Similarly, while the contribution of iron is increasingly advocated, identifying its role in disease progression remains challenging mainly due to the lack of valid model. In this study, we created Parkinson-like conditions in a human neuron model and conducted preliminary studies on iron-related parameters to assess whether these cells replicated iron accumulation observed in Parkinsonism. Methods: ReNcell VM (human neural progenitor) were differentiated into dopaminergic neurons (dDCNs) and treated with neurotoxin 6-hydroxy dopamine (100 μM) to mimic Parkinsonism. Total intracellular, mitochondrial and cytoplasmic iron was measured by ferrozine assay. Expression of iron-related genes TFRC, SLC40A1, HAMP and SLC25A37 were assessed through real-time PCR. Results: Data showed that the treated dDCNs accumulated iron over time and exceeded levels measured in untreated dDCNs by 2.5-fold at 48 h (p<0.02). Following the treatment, the treated cells showed lower expression of TFRC (p<0.05), but substantially higher mRNA expressions of SLC40A1 (9-fold; p<0.02) and HAMP (5.7-fold; p<0.05), along with higher intracellular iron (p<0.05). Higher iron accumulation in the mitochondria than cytosol (p<0.05), was also observed with increased expression of the mitochondrial iron-importer SLC25A37 (p=0.08). Conclusion: Our Parkinsonian model demonstrates iron accumulation and elevated HAMP expression as previously described in PD phenotype. The observed mitochondrial iron shuttling, which is proposed to be one of the primary contributors of oxidative stress in PD, calls for further investigation. The differences observed in distribution of iron in our human model and with the expression of major iron-related proteins, indicate that our model reproduces the disease state successfully, and suggests that further study could help in advancing our understanding of PD.