ABSTRACT
Fast Scan Cyclic Voltammetry (FSCV) has been used for decades as a neurochemical tool for in vivo detection of phasic changes in electroactive neurotransmitters in animal models. Recently, multiple research groups have initiated human neurochemical studies using FSCV or demonstrated interest in bringing FSCV into clinical use. However, there remain technical challenges that limit clinical implementation of FSCV by creating barriers to appropriate scientific rigor and patient safety. In order to progress with clinical FSCV, these limitations must be first addressed through (1) appropriate pre-clinical studies to ensure accurate measurement of neurotransmitters and (2) the application of a risk management framework to assess patient safety. The intent of this work is to bring awareness of the current issues associated with FSCV to the scientific, engineering, and clinical communities and encourage them to seek solutions or alternatives that ensure data accuracy, rigor and reproducibility, and patient safety.
ABSTRACT
A large body of evidence suggests that peroxisome proliferator-activated receptor (PPAR) agonists may improve some of the pathological features of Parkinson's disease (PD). In the present study, we evaluated the effects of the PPAR-α agonist fenofibrate (100mg/kg) and PPAR-γ agonist pioglitazone (30mg/kg) in a rat model of parkinsonism induced by intranigral 1-methyl-4-phenyl-1,2,3,6-tetrahyropyridine (MPTP). Male Wistar rats were pretreated with both drugs for 5 days and received an infusion of MPTP. The experiments were divided into two parts. First, 1, 7, 14, and 21 days after surgery, the animals were submitted to the open field test. On days 21 and 22, the rats were subjected to the forced swim test and two-way active avoidance task. In the second part of the study, 24h after neurotoxin administration, immunohistochemistry was performed to assess tyrosine hydroxylase activity. The levels of dopamine and its metabolites in the striatum were determined using high-performance liquid chromatography, and fluorescence detection was used to assess caspase-3 activation in the substantia nigra pars compacta (SNpc). Both fenofibrate as pioglitazone protected against hypolocomotion, depressive-like behavior, impairment of learning and memory, and dopaminergic neurodegeneration caused by MPTP, with dopaminergic neuron loss of approximately 33%. Fenofibrate and pioglitazone also protected against the increased activation of caspase-3, an effector enzyme of the apoptosis cascade that is considered one of the pathological features of PD. Thus, PPAR agonists may contribute to therapeutic strategies in PD.