The Redox Stress Test: A novel technique reveals oxidative stress in Parkinson’s disease
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Abstract
A novel Redox Stress Test has been developed to identify symptoms of diseases associated with oxidative stress by observing symptom changes induced by short-term activation of the transcription factor Nrf2, to restore redox homeostasis. The Nrf2 pathway is triggered by a herbal preparation, Broccoli Seed Tea, developed to deliver a therapeutic dose of highly bioavailable sulforaphane, a potent activator of Nrf2. We discuss the rationale behind the tea and describe the methods used to optimise the bioavailability of sulforaphane to match the pharmacodynamics of Nrf2 activation. When consumed by people with Parkinson’s disease, the Redox Stress Test induced powerful and concurrent attenuation of a diverse group of Parkinson’s non-motor symptoms, including fatigue, constipation and urinary urgency. Motor symptoms were strictly unaffected. This observation indicates that oxidative stress may be a common factor contributing to non-motor symptoms involving sites in the CNS and peripheral organs. We tentatively interpret the results in terms of a hypothetical model for Parkinson’s Syndrome which we describe as a multisystem redox disorder with reservoirs of the disease in peripheral organs as well as in the brain. Eliminating the disease in peripheral organs is therefore a prerequisite to stopping disease progression in the brain. According to this model, the redox disorder in the brain provokes progressive neurological damage, which is not recognised as such in the early years. More specific neurological symptoms only come to light many years later, when damage to dopaminergic neurons creates a dopamine deficiency which eventually exceeds the threshold required for normal motor control, generating a new coherent group of neurological symptoms which define movement disorder. Given the apparent ease with which oxidative stress can be quenched in several locations simultaneously, we briefly discuss possible implications for public health, medical research, patients and patient advocacy groups. We note that the Redox Stress Test may have the potential to explore symptoms of other diseases where oxidative stress is believed to play a major role, although this remains subject to validation by further research.
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