Functional Imaging and Physiological Modulation with Acupuncture in Parkinson’s Disease and Nonhuman Primate Models of Dopamine Dysfunction

Here we review functional imaging and neurophysiological evidence for the preclinical and clinical use of electroacupuncture, a non-pharmaceutical-based therapeutic strategy, to relieve parkinsonian symptoms. Outcomes from those studies provide evidence that the effect of electroacupuncture can be objectively measured in nonhuman primate models of Parkinson’s disease and in patients with Parkinson’s disease. In addition, the evidence continues to support that electroacupuncture can be used in preclinical and clinical studies simply, safely, and effectively as an alternative and complementary treatment for disorders in Parkinson’s disease

Objectively Measuring Effects of Electro-Acupuncture in Parkinsonian Rhesus Monkeys

Acupuncture has increasingly been used as an alternative therapy for treatment of Parkinson’s disease (PD). However, the efficacy of acupunture for PD still remains unclear. The present study was designed to objectively and safely monitor anti-parkinsonian effects of electroacupuncture (EA) and brain activity in nonhuman primates modeling human PD. Six middle-aged rhesus monkeys were extensively studied by a computerized behavioral testing battery and by pharmacological MRI (phMRI) scans with specific dopaminergic drug stimulations. All animals were evaluated for behavior and phMRI responses under normal, parkinsonian, parkinsonian with EA treatment and parkinsonian after EA treatment conditions. Stable parkinsonian features were observed in all animals prior to entering the EA study and positive responses to levodopa (L-dopa) challenge were also seen in all animals. The results demonstrated that chronic EA treatments could significantly improve the movement speed and the fine motor performance time during the period of EA treatments, and the effectiveness of EA could be detected even 3 months after the EA treatment. The phMRI data revealed that chronic EA treatments could alter neuronal activity in the striatum, primary motor cortex (M1), cingulate gyrus and global pallidus externa (GPe) in the ipsilateral hemisphere to MPTP lesions. As seen in the changes of parkinsonian features, the residual effects of phMRI responses to apomorphine (APO) challenge could also be found in the aforementioned areas. The results strongly suggest that anti-parkinsonian effects of EA can be objectively assessed, and the method used in the present study could be translated into the human clinic with some minor modifications

Acupuncture

Acupuncture may have about 4000 years of history, but it has only been clinically accepted in the West for some 40 years. Acupuncture receives both praise from its users and skepticism from its critics. High-quality scientific studies have advanced, but the technique of acupuncture in health services has stagnated. In this current scenario of contrasts, Acupuncture - Resolving Old Controversies and Pointing New Pathways intends to be a modern reference for scholars, without totally exhausting the subject. The editors expect this work to assist with the advancement of the scientific understanding and clinical usage of acupuncture. The authors are well versed in the subject and, along with literature reviews, are able to add their own impressions. In this book, some traditional fundamentals of ancient Asian medicine are translated into the current scientific knowledge of neurophysiology and mechanisms of action. Specific variations of acupuncture, such as the scalp microsystem technique, are discussed and explained. Practical aspects, such as education on acupuncture, are enriched with descriptions of novel treatments. The therapeutic use of acupuncture and related techniques is explored regarding their incorporation into a comprehensive integrative medicine approach. As editors, we thank the contributing authors for their exquisite work, and we congratulate IntechOpen for its efforts in book production. For you, the readers, we hope to match the trust you put in this work, and we hope you find it useful

The Noradrenergic System in Parkinson’s Disease

Nowadays it is well accepted that in Parkinson's disease (PD), the neurodegenerative process occurs in stages and that damage to other areas precedes the neuronal loss in the substantia nigra pars compacta, which is considered a pathophysiological hallmark of PD. This heterogeneous and progressive neurodegeneration may explain the diverse symptomatology of the disease, including motor and non-motor alterations. In PD, one of the first areas undergoing degeneration is the locus coeruleus (LC). This noradrenergic nucleus provides extensive innervation throughout the brain and plays a fundamental neuromodulator role, participating in stress responses, emotional memory, and control of motor, sensory, and autonomic functions. Early in the disease, LC neurons suffer modifications that can condition the effectiveness of pharmacological treatments, and importantly, can lead to the appearance of common non-motor symptomatology. The noradrenergic system also exerts anti-inflammatory and neuroprotective effect on the dopaminergic degeneration and noradrenergic damage can consequently condition the progress of the disease. From the pharmacological point of view, it is also important to understand how the noradrenergic system performs in PD, since noradrenergic medication is often used in these patients, and drug interactions can take place when combining them with the gold standard drug therapy in PD, L-3,4-dihydroxyphenylalanine (L-DOPA). This review provides an overview about the functional status of the noradrenergic system in PD and its contribution to the efficacy of pharmacological-based treatments. Based on preclinical and clinical publications, a special attention will be dedicated to the most prevalent non-motor symptoms of the disease.This study was supported by grants from the Basque Government (PIBA 2019-38, IT1345-19), UPV/EHU (PPGA19/15), and Spanish Government (SAF2016‐77758‐R [AEI/FEDER, UE]). EP-R has a fellowship from the Basque Country and SV-S from the UPV/EHU

Vulnerability to cognitive, neurotoxic and neuroinflammatory effects of toxins that induce Parkinson's disease after administration of amphetamine-related drugs in mice

Clinical observations report a higher propensity to develop Parkinson’s disease (PD) in amphetamine users. 3,4-Methylenedioxymethamphetamine (MDMA) is an amphetamine-related drug which may have neuroinflammatory and neurotoxic effects. The present study was aimed at evaluating in mice whether administration of MDMA during adolescence might influence neurotoxicity towards dopaminergic neurons and neuroinflammatory effects of 1-methyl-4- phenyl-1,2,3,6-tetrahydropyridine (MPTP), a toxin known to induce PD in humans, in motor, limbic and cortical areas, and consequently affects cognitive performance. Mice received MDMA (10 mg/kg, twice a day/a week) for 9 weeks, followed by MPTP (20 mg/kg × 4 administrations), starting 2 weeks after MDMA discontinuation. Activation of astroglia and microglia by GFAP and CD11b immunohistochemistry in motor areas, as substantia nigra compacta (SNc) and striatum, limbic and cortical areas, as hippocampus and medial prefrontal cortex (mPFC), was assessed. Degeneration of dopaminergic neurons by tyrosine hydroxylase (TH) immunohistochemistry in SNc and striatum was also evaluated. Neurochemical evaluations were paired with assessment of cognitive performance by means of the novel object recognition (NOR) and spontaneous alternation in a Y-maze tests. MPTP administration to MDMA-pretreated mice elicited a stronger increase in CD11b and GFAP levels in motor, limbic and cortical areas, and a stronger decrease of TH-positive neurons and fibers in motor areas, compared with either substance administered alone. Furthermore, NOR performance in the same group was lower, compared with mice that received either substance alone. Results demonstrate that MDMA administration during adolescence influence negatively MPTP effects on motor, limbic and cortical areas and result in cognitive impairment

Evolution of Extra-Nigral Damage Predicts Behavioural Deficits in a Rat Proteasome Inhibitor Model of Parkinson's Disease

Establishing the neurological basis of behavioural dysfunction is key to provide a better understanding of Parkinson's disease (PD) and facilitate development of effective novel therapies. For this, the relationships between longitudinal structural brain changes associated with motor behaviour were determined in a rat model of PD and validated by post-mortem immunohistochemistry. Rats bearing a nigrostriatal lesion induced by infusion of the proteasome inhibitor lactacystin into the left-medial forebrain bundle and saline-injected controls underwent magnetic resonance imaging (MRI) at baseline (prior to surgery) and 1, 3 and 5 weeks post-surgery with concomitant motor assessments consisting of forelimb grip strength, accelerating rotarod, and apormorphine-induced rotation. Lactacystin-injected rats developed early motor deficits alongside decreased ipsilateral cortical volumes, specifically thinning of the primary motor (M1) and somatosensory cortices and lateral ventricle hypertrophy (as determined by manual segmentation and deformation-based morphometry). Although sustained, motor dysfunction and nigrostriatal damage were maximal by 1 week post-surgery. Additional volume decreases in the ipsilateral ventral midbrain; corpus striatum and thalamus were only evident by week 3 and 5. Whilst cortical MRI volume changes best predicted the degree of motor impairment, post-mortem tyrosine hydroxylase immunoreactivity in the striatum was a better predictor of motor behaviour overall, with the notable exception of performance in the accelerating rotarod, in which, M1 cortical thickness remained the best predictor. These results highlight the importance of identifying extra-nigral regions of damage that impact on behavioural dysfunction from damage to the nigrostriatal system

RESTORATION OF MOTOR AND NON-MOTOR FUNCTIONS BY NEUROTROPHIC FACTORS IN NONHUMAN PRIMATES WITH DOPAMINE DEPLETION

Parkinson’s disease (PD) is a progressive debilitating neurodegenerative disorder characterized by resting tremor, rigidity, bradykinesia and postural instability. As the disease progresses there is a loss of dopamine (DA) neurons in the substantia nigra projecting to the various forebrain and sub-cortical regions. Current treatments for PD are unable to prevent or curtail the neurodegenerative process; so rescuing remaining dopamine in the mid-brain has been the recent focus of research examining the effectiveness of neurotrophic factors (NTFs) in the treatment of PD. In this dissertation, the ability of three novel, recently discovered NTFs to restore DA neurons and motor function in a nonhuman primate model of PD was examined. The NTFs were Cerebral Dopamine Neurotrophic Factor (CDNF) and two variants of Neurturin (NRTN), N2 and N4, that have mutations that prevent binding to heparin sulfate binding sites in the brain. These studies used the unilateral low dose (0.15 ± 0.001 mg/kg) monkey 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD to cause loss of DA neurons. Six groups of monkeys were studied: vehicle-treated (negative control), Glial Cell-line Derived Neurotropic Factor (GDNF, positive control), two groups of CDNF-treated monkeys (450 μg and 150 μg), and N2 and N4-treated groups. After MPTP, monkeys developed moderate symptoms of PD (PD rating scale score=7.9±0.5 on a scale of 0-22, p<0.001), motor dysfunction and increased daytime sleepiness. After three months of infusions, all three NTFs (150 μg CDNF, N2 and N4) significantly increased the number of DA neurons in the substantia nigra, p=0.03, and improved parkinsonian symptoms measured by rating scale, p<0.001. Most motor functions were significantly correlated with the number of DA neurons in the substantia nigra. N4 significantly improved daytime sleep duration, bouts and wake-latency (p=0.02, p=0.06 and p=0.02, respectively). In summary, CDNF, N2 and N4 trophic factors are neurorestorative to DA neurons, motor function is tightly correlated with DA neuronal number, and N4 improved the non-motor symptom of increased daytime sleepiness in this monkey PD model. These factors hold promise for clinical therapy for PD patients

Études de la subthalamotomie comme traitement des dyskinésies chez le primate parkinsonien

La présente thèse comprend une étude des mécanismes neurochimiques d’une approche chirurgicale, la subthalamotomie, pour le traitement de la maladie de Parkinson et les dyskinésies induites à la L-DOPA. Nous avons cherché à identifier, à l’aide de quelques hypothèses de recherche, les changements biochimiques dans les ganglions de la base induits par la lésion du noyau sous-thalamique. Nous avons utilisé un modèle de singe parkinsonien traité à la L-DOPA et ayant reçu une subthalamotomie unilatérale. Nos résultats démontrent que la subthalamotomie potentialise la réponse à faible dose de L-DOPA et que cette potentialisation serait entre autre régulée par le récepteur dopaminergique D1 et les récepteurs glutamatergiques métabotropiques. Ces données apportent de nouveaux éléments aidant à mieux comprendre les mécanismes de cette chirurgie pour le traitement des dyskinésies induites à la L-DOPA. De telles connaissances ouvrent la porte à de nouvelles stratégies pour augmenter la réponse chirurgicale du patient.Lesion of the subthalamic nucleus, also called subthalamotomy, is surgical therapy offered to parkinsonian patients refractory to L-DOPA or for whom L-DOPA-induced dyskinesias become disabling. Its mechanisms remain however largely unknown. In order to better understand the biochemical and cellular changes underlying subthalamotomy, we used an Parkinson’s disease animal model, the MPTP monkey. Chronic administration of L-DOPA in this animal model induces dyskinesias, as those seen in parkinsonian patients. The monkeys used in this study displayed such side effects and took part of different pharmacological trials to reduce these dyskinesias before undergoing surgery. Thus, we replicated the clinical situation where patients receive such surgery when all the other pharmacological treatments have failed. These monkeys received a unilateral subthalamotomy, the non-lesioned side served as an intra-animal control. Antiparkinsonian response to low dose of L-DOPA was potentiated by subthalamotomy. Then, we studied by autoradiography the D1 and D2 dopaminergic receptors, ionotropic NMDA (NR1/NR2B) and AMPA, metabotropic mGluR2/3 and mGluR5 glutamatergic receptors, and the dopaminergic transporter (DAT) using respectively the selective radioligands [3H]-SCH-23390, [3H]-Raclopride, [3H]-Ro 25-6981, [3H]-Ro 48-8587, [3H]-LY-341495, [3H]-ABP688 and [125I]-RTI-121. We measured by in situ hybridization the D1, D2 and preproenkephalin mRNAs using oligonucleotides as well as preprodynorphin mRNA using a riboprobe. We also assessed the dopamine and its metabolites by high-performance liquid chromatography. Finally, we measured the proteins ERK1 and ERK2, involved in intracellular signaling, and their respective phosphorylation state, as well as DARPP-32 by Western blot. Our results show that the dopamine D1 receptor, but not D2, as well as the metabotropic glutamate receptors are involved in the behavioral effects of subthalamotomy. This data suggest that the potentiation of response to L-DOPA after subthalamotomy would be due to changes in the direct pathway of the model of basal ganglia and in the subthalamic output. Our results open new and exciting pathways to explore on subthalamotomy, as well as other surgeries that are offered to disabled patients with movement disorders, whether these surgeries are lesional or with implantable stimulation devices

TARGETING AXON GROWTH FROM NEURONS TRANSPLANTEDINTO THE CENTRAL NERVOUS SYSTEM

Damage to the adult mammalian central nervous system (CNS), either by traumatic injury or disease, usually results in permanent sensory and/or motor deficits. Regeneration of neural circuits is limited both by the lack of growthpromoting molecules and by the presence of growth-inhibitory molecules in the mature brain and spinal cord. The research described here examines the therapeutic potential of viral vectors and neuronal transplants to reconstruct damaged neural pathways in the CNS. Experimental neural transplantation techniques often fall short of expectations because of limited transplant survival and insufficient neurite outgrowth to repair connections and induce behavioral recovery. These shortcomings are addressed in the current studies by virus-mediated expression of cell-specific neurotrophic and guidance molecules in the host brain prior to cell transplantation. The initial proof-of-principle studies show that viral vectors can be used to create axon-guidance pathways in the adult mammalian brain. With such pathways in place, subsequent transplantation of neurons leads to longdistance, targeted outgrowth of neurites. Application of this technique to a rat model of Parkinsons disease demonstrates that circuit reconstruction leads to functional recovery. For this study, rats were lesioned on one side of their brain with 6-hydroxydopamine to produce a hemiparkinsonian state. The motor deficit was confirmed by amphetamine-induced rotation testing and spontaneous motor asymmetry testing. The rats were then divided into experimental groups to receive lentivirus injections along a path between the substantia nigra (SN) and the striatum to express glial cell-line derived neurotrophic factor (GDNF), GDNF family receptor alpha-1 (GFR1), netrin-1 or green fluorescent protein (GFP, control). One group received combination injections of lenti-GDNF and lenti-GFR1. One week after virus injections, animals received transplants of embryonic midbrain dopaminergic neurons into their SNs. They were tested for motor asymmetry every two weeks for a total of eight weeks and then brain tissue was harvested for immunohistochemical analysis. Results demonstrate that virus-induced expression of GDNF and GFR1 supports growth of dopaminergic fibers from cells transplanted into the SN all the way to the striatum, and these animals have a significant reduction in both drug-induced and spontaneous motor asymmetry