DA-9805 protects dopaminergic neurons from endoplasmic reticulum stress and inflammation.

Parkinson's disease (PD) is a multifactorial neurodegenerative disease with damages to mitochondria and endoplasmic reticulum (ER), followed by neuroinflammation. We previously reported that a triple herbal extract DA-9805 in experimental PD toxin-models had neuroprotective effects by alleviating mitochondrial damage and oxidative stress. In the present study, we investigated whether DA-9805 could suppress ER stress and neuroinflammation in vitro and/or in vivo. Pre-treatment with DA-9805 (1 µg/ml) attenuated upregulation of glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP) and cleaved caspase-3 in SH-SY5Y neuroblastoma cells treated with thapsigargin (1 µg/ml) or tunicamycin (2 µg/ml). In addition, DA-9805 prevented the production of IL-1ß, IL-6, TNF-α and nitric oxide through inhibition of NF-κB activation in BV2 microglial cells stimulated with lipopolysaccharides (LPS). Intraperitoneal injection of LPS (10 mg/kg) into mice can induce acute neuroinflammation and dopaminergic neuronal cell death. Oral administration of DA-9805 (10 or 30 mg/kg/day for 3 days before LPS injection) prevented loss of dopaminergic neurons and activation of microglia and astrocytes in the substantia nigra in LPS-injected mouse models. Taken together, these results indicate that DA-9805 can effectively prevent ER stress and neuroinflammation, suggesting that DA-9805 is a multitargeting and disease-modifying therapeutic candidate for PD.

Effects of bee venom and dopamine-loaded nanoparticles on reserpine-induced Parkinson's disease rat model.

Parkinson's disease (PD) is a progressive chronic neurodegenerative condition characterized by the loss of dopaminergic neurons within the substantia nigra. Current PD therapeutic strategies are mainly symptomatic and can lead to motor complications overtime. As a result, alternative medicine may provide an effective adjuvant treatment for PD as an addition to or as a replacement of the conventional therapies. The aim of this work was to evaluate the effects of Bee Venom (BV) and dopamine (DA)-loaded nanoparticles in a reserpine-induced animal model of PD. After inducing PD with reserpine injection, different groups of male rats were treated with L-Dopa, BV, DA-nanoparticles. Our findings showed that BV and DA-nanoparticles administration restored monoamines, balanced glutamate/GABA levels, halted DNA fragmentation, decreased pro-inflammatory mediators (IL-1ß and TNF-α), and elevated anti-inflammatory mediators (PON1) and neurotropic factor (BDNF) levels in comparison with conventional therapy of PD. Furthermore, in a reserpine-induced PD rat model, the ameliorative effects of BV were significantly superior to that of DA-nanoparticles. These findings imply that BV and DA-nanoparticles could be useful as adjuvant treatments for PD.

Treatment of subcutaneous nodules after infusion of apomorphine; a biopsy-controlled study comparing 4 frequently used therapies.

This study aimed to provide clinical evidence for existing treatments of subcutaneous nodules after subcutaneous infusion of apomorphine, using a biopsy-controlled prospective crossover design of four treatments. We demonstrated that dilution of apomorphine significantly improved patient satisfaction, while subcutaneous hydrocortisone reduced nodule size, however with no differences in the histopathology.

Treatment Options for Motor and Non-Motor Symptoms of Parkinson's Disease.

Parkinson's disease (PD) usually presents in older adults and typically has both motor and non-motor dysfunctions. PD is a progressive neurodegenerative disorder resulting from dopaminergic neuronal cell loss in the mid-brain substantia nigra pars compacta region. Outlined here is an integrative medicine and health strategy that highlights five treatment options for people with Parkinson's (PwP): rehabilitate, therapy, restorative, maintenance, and surgery. Rehabilitating begins following the diagnosis and throughout any additional treatment processes, especially vis-à-vis consulting with physical, occupational, and/or speech pathology therapist(s). Therapy uses daily administration of either the dopamine precursor levodopa (with carbidopa) or a dopamine agonist, compounds that preserve residual dopamine, and other specific motor/non-motor-related compounds. Restorative uses strenuous aerobic exercise programs that can be neuroprotective. Maintenance uses complementary and alternative medicine substances that potentially support and protect the brain microenvironment. Finally, surgery, including deep brain stimulation, is pursued when PwP fail to respond positively to other treatment options. There is currently no cure for PD. In conclusion, the best strategy for treating PD is to hope to slow disorder progression and strive to achieve stability with neuroprotection. The ultimate goal of any management program is to improve the quality-of-life for a person with Parkinson's disease.

Surgical Treatment of Parkinson's Disease: Devices and Lesion Approaches.

Surgical treatments have transformed the management of Parkinson's disease (PD). Therapeutic options available for the management of PD motor complications include deep brain stimulation (DBS), ablative or lesioning procedures (pallidotomy, thalamotomy, subthalamotomy), and dopaminergic medication infusion devices. The decision to pursue these advanced treatment options is typically done by a multidisciplinary team by considering factors such as the patient's clinical characteristics, efficacy, ease of use, and risks of therapy with a goal to improve PD symptoms and quality of life. DBS has become the most widely used surgical therapy, although there is a re-emergence of interest in ablative procedures with the introduction of MR-guided focused ultrasound. In this article, we review DBS and lesioning procedures for PD, including indications, selection process, and management strategies.

An update on the use of non-ergot dopamine agonists for the treatment of Parkinson's disease.

INTRODUCTION: Long-term treatment of Parkinson's disease (PD) with levodopa is hampered by motor complications related to the inability of residual nigrostriatal neurons to convert levodopa to dopamine (DA) and use it appropriately. This generated a tendency to postpone levodopa, favoring the initial use of DA agonists, which directly stimulate striatal dopaminergic receptors. Use of DA agonists, however, is associated with multiple side effects and their efficacy is limited by suboptimal bioavailability. AREAS COVERED: This paper reviewed the latest preclinical and clinical findings on the efficacy and adverse effects of non-ergot DA agonists, discussing the present and future of this class of compounds in PD therapy. EXPERT OPINION: The latest findings confirm the effectiveness of DA agonists as initial treatment or adjunctive therapy to levodopa in advanced PD, but a more conservative approach to their use is emerging, due to the complexity and repercussions of their side effects. As various factors may increase the individual risk to side effects, assessing such risk and calibrating the use of DA agonists accordingly may become extremely important in the clinical management of PD, as well as the availability of new DA agonists with better profiles of safety and efficacy.

The preclinical discovery and development of opicapone for the treatment of Parkinson's disease.

INTRODUCTION: Opicapone (OPC) is a well-established catechol-O-methyltransferase (COMT) inhibitor that is approved for the treatment of Parkinson's disease (PD) associated with L-DOPA/L-amino acid decarboxylase inhibitor (DDI) therapy allowing for prolonged activity due to a more continuous supply of L-DOPA in the brain. Thus, OPC decreases fluctuation in L-DOPA plasma levels and favors more constant central dopaminergic receptor stimulation, thus improving PD symptomatology. AREAS COVERED: This review evaluates the preclinical development, pharmacology, pharmacokinetics and safety profile of OPC. Data was extracted from published preclinical and clinical studies published on PUBMED and SCOPUS (Search period: 2000-2019). Clinical and post-marketing data are also evaluated. EXPERT OPINION: OPC is a third generation COMT inhibitor with a novel structure. It has an efficacy and tolerability superior to its predecessors, tolcapone (TOL) and entacapone (ENT). It also provides a safe and simplified drug regimen that allows neurologists to individually adjust the existing daily administration of L-DOPA. OPC is indicated as an adjunctive therapy to L-DOPA/DDI in patients with PD and end-of-dose motor fluctuations who cannot be stabilized on those combinations.

Pharmacokinetics and pharmacodynamics of levodopa/carbidopa cotherapies for Parkinson's disease.

Introduction: Parkinson's disease is a chronic, neurodegenerative disease entity with heterogeneous features and course. Levodopa is the most efficacious dopamine substituting drug. Particularly, long-term application of oral levodopa/decarboxylase inhibitor formulations sooner or later supports onset of fluctuations of movement. It also shifts levodopa turnover to O-methylation, which impairs human methylation capacity and increases oxidative stress.Areas covered: This narrative review summarizes pharmacokinetic and pharmacodynamic features of available levodopa cotherapies on the basis of a literature search with the terms L-dopa, inhibitors of catechol-O-methyltransferase and monoamine oxidase-B.Expert opinion: Long-term levodopa/dopa decarboxylase inhibitor application with concomitant inhibition of both, catechol-O-methyltransferase and monoamine oxidase-B supports a more continuous dopamine substitution, which ameliorates fluctuations of motor behavior. This triple combination also enhances both, antioxidative defense and methylation capacity. Inhibition of monoamine oxidase-B reduces generation of oxidative stress in the brain. Constraint of catechol-O-methyltransferase reduces homocysteine synthesis due to diminished consumption of methyl groups for levodopa turnover at least in the periphery. An additional nutritional supplementation with methyl group donating and free radical scavenging vitamins is recommendable, when future drugs are developed for long-term levodopa/dopa decarboxylase treated patients. Personalized medicine treatment concepts shall also consider nutritional aspects of Parkinson's disease.

In vitro and in vivo evaluation of levodopa-loaded nanoparticles for nose to brain delivery.

Parkinson's disease (PD) is a neurodegenerative disease which is characterized by the loss of dopaminergic neurons in the brain. Levodopa is the drug of choice in the treatment of PD but it exhibits low oral bioavailability (30%) and very low brain uptake due to its extensive metabolism by aromatic amino acid decarboxylase in the peripheral circulation. Moreover, levodopa has psychic, gastrointestinal, and cardiovascular side effects, and most importantly, short and frequent stimulation of dopamine receptors lead to undesirable conditions such as dyskinesia over time. The challenges are to increase the therapeutic efficiency, the bioavailability and decreasing the unfavourable side effects of levodopa. Biocompatible nano-sized drug carriers could address these challenges at molecular level. For this purpose, levodopa-loaded Poly (lactide-co-glycolide) acid nanoparticles were prepared by double emulsion-solvent evaporation method for nose to brain drug delivery. Parameters such as homogenization speed, and external and internal phase content were modified to reach the highest loading efficiency. F1-1 coded formulation showed prolonged release up to 9 h. Carbodiimide method was used for surface modification studies of nanoparticles. The efficacy of the selected nanoparticle formulation has been demonstrated by in vivo experiments in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine induced PD model in mice.

Efficacy of oral administration of licorice as an adjunct therapy on improving the symptoms of patients with Parkinson's disease, A randomized double blinded clinical trial.

ETHNOPHARMACOLOGICAL RELEVANCE: Licorice preparations are used as neuroprotective remedies in Persian ethnomedicine, in order to prevent from disabilities in neurodegenerative conditions like Parkinson's disease (PD). AIM OF THE STUDY: This study was designed to determine the licorice (root of Glycyrrhiza glabra L.) effectiveness as an adjunct treatment in the PD management. MATERIAL AND METHODS: In this double-blinded trial, 128 patients were assessed for eligibility criteria. Seventy-eight patients were ineligible and 11 of them refused from participating. Thirty-nine PD patients (YAHR staging ≤ 3) were divided into two groups by random. The patients received oral licorice or placebo syrups with a dose of 5 cc, twice a day for 6 months. High-performance liquid chromatography and spectrophotometric instruments determined licorice syrup constituents. The patients' situation for Unified Parkinson's rating scale (UPDRS) was assessed every 6 weeks for the duration of six months. In addition, patients' blood pressure, blood glucose, sodium and potassium levels, quality of life and dizziness were determined. RESULTS: Six weeks after intervention, total UPDRS, daily activities and tremor were significantly improved with a considerable effect size. A significant better motor test and rigidity scores were observed 4 months after licorice intake (p > 0.05). No electrolyte abnormality, significant changes in blood pressure or blood glucose levels were observed during the study. Each 5cc of syrup contained 136 mg of licorice extract with 12.14 mg glycyrrhizic acid, and also 136 µg of polyphenols. CONCLUSION: The licorice intake could improve the symptoms in PD patients without serious adverse events.

The parthenolide derivative ACT001 synergizes with low doses of L-DOPA to improve MPTP-induced Parkinson's disease in mice.

L-3,4-dihydroxyphenylalanine (L-DOPA) is currently the main drug used to treat Parkinson's disease (PD). However, long-term use of l-DOPA causes substantial side effects, and we hope to find a biological active ingredient that synergizes with a low-dose of l-DOPA to achieve the same therapeutic effect as that of a high-dose of l-DOPA. The natural product parthenolide (PTL) is the active ingredient in the medicinal plant feverfew (Tanacetum parthenium) and has antioxidant and anti-inflammatory properties. ACT001, a fumarate salt form of dimethylaminomicheliolide (DMAMCL), is a derivative of parthenolide and has comparable effects to those of PTL but exhibits higher stability in the plasma and is available at a lower cost. In our study, we used ACT001 in combination with l-DOPA to treat 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced Parkinson's disease in mice. Specifically, ACT001 significantly reduced motor dysfunction and dopaminergic neurodegeneration in MPTP-treated mice. Furthermore, ACT001 abolished MPTP-induced α-synuclein overexpression, astrocyte activation and interleukin-1ß (IL-1ß) production in the substantia nigra and striatum of the mouse brain. In addition, ACT001 increased the levels of the anti-apoptotic signalling molecule Bcl-2 and the pAkt/Akt ratio and reduced the levels of the pro-apoptotic signalling molecule Bax and the activation of Caspase3 in the substantia nigra and striatum. We found that the effects of the co-administration of ACT001 and l-DOPA (5 mg/kg) were equivalent to those of the administration of 8 mg/kg l-DOPA in MPTP-induced Parkinson's disease in mice. Then, this evidence suggests that l-DOPA + ACT001 may be used for the treatment of PD.

NF-κB-Mediated Neuroinflammation in Parkinson's Disease and Potential Therapeutic Effect of Polyphenols.

Different animal and human studies from last two decades in the case of Parkinson's disease (PD) have concentrated on oxidative stress due to increased inflammation and cytokine-dependent neurotoxicity leading to induction of dopaminergic (DA) degeneration pathway in the nigrostriatal region. Chronic inflammation, the principle hallmark of PD, forms the basis of neurodegeneration. Aging in association with activation of glia due to neuronal injury, perhaps because of immune alterations and genetic predispositions, leads to deregulation of inflammatory pathways premising the onset of PD. A family of inducible transcription factors, nuclear factor-κB (NF-κB), is found to show expression in various cells and tissues, such as microglia, neurons, and astrocytes which play an important role in activation and regulation of inflammatory intermediates during inflammation. Both canonical and non-canonical NF-κB pathways are involved in the regulation of the stimulated cells. During the prodromal/asymptomatic stage of age-associated neurodegenerative diseases (i.e., PD and AD), chronic neuroinflammation may act silently as the driver of neuronal dysfunction. Though research has provided an insight over age-related neurodegeneration in PD, elaborative role of NF-κB in neuroinflammation is yet to be completely understood and thus requires more investigation. Polyphenols, a group of naturally occurring compound in medicinal plants, have gained attention because of their anti-oxidative and anti-neuroinflammatory properties in neurodegenerative diseases. In this aspect, this review highlights the role of NF-κB and the possible therapeutic roles of polyphenols in NF-κB-mediated neuroinflammation in PD.

Coumarin analogue 3-methyl-7H-furo[3,2-g] chromen-7-one as a possible antiparkinsonian agent / El análogo de cumarina 3-metil-7H-furo[3,2-g]cromen-7-ona, un posible agente antiparkinsoniano

INTRODUCTION: Parkinson's disease is the second most common neurodegenerative disease. Monoamine oxidase B inhibitors are used in the treatment of this disease concomitantly with levodopa or as monotherapy. Several substituted coumarins have shown activity as inhibitors of monoamine oxidase B. OBJECTIVE: To evaluate the possible antiparkinsonian effects of the coumarin analogue FCS005 (3-methyl-7H-furo[3,2-g]chromen-7-one) in mouse models, as well as its inhibitory activity towards monoamine oxidases (MAO) and its antioxidant activity. MATERIALS AND METHODS: FCS005 was synthesized and the reversal of hypokinesia was evaluated in the reserpine and levodopa models. Moreover, in the haloperidol model, its anticataleptic effects were evaluated. Additionally, the monoamine oxidase inhibitory activity and antioxidant activity of FCS005 were evaluated using in vitro and ex vivo studies, respectively. RESULTS: FCS005 (100 mg/kg) caused the reversal of hypokinesia in the reserpine and levodopa models. This furocoumarin also presented anti-cataleptic effects at the same dose. Besides, it showed selective inhibitory activity towards the MAO-B isoform and antioxidant activity. CONCLUSION: These results attribute interesting properties to the compound FCS005. It is important to continue research on this molecule considering that it could be a potential antiparkinsonian agent.

Introducción. El segundo trastorno neurodegenerativo más común es la enfermedad de Parkinson. Los inhibidores de la monoamino oxidasa B se emplean en el tratamiento de esta enfermedad en monoterapia o concomitantemente con levodopa. Varios compuestos cumarínicos han mostrado actividad como inhibidores de la monoamino oxidasa B. Objetivo. Evaluar los posibles efectos antiparkinsonianos del análogo de la cumarina FCS005 (3-methyl-7H-furo[3,2-g]chromen-7-one) en modelos de ratones, la actividad inhibitoria frente a las monoamino oxidasas (MAO) y la actividad antioxidante. Materiales y métodos. Se sintetizó la furanocumarina FCS005 y, en los modelos de reserpina y levodopa, se evaluó si producía reversión de la hipocinesia; en el modelo de haloperidol se evaluaron sus efectos anticatalépticos. Además, se evaluó in vitro la actividad inhibidora de MAO y, ex vivo, la actividad antioxidante del compuesto FCS005. Resultados. El compuesto FCS005 en dosis de 100 mg/kg produjo la remisión de la hipocinesia en los modelos de reserpina y de levodopa. Esta furanocumarina presentó efectos anticatalépticos con la misma dosis. Además, mostró tener actividad inhibitoria selectiva sobre la MAO B, así como efectos antioxidantes. Conclusión. Los resultados evidenciaron propiedades interesantes del compuesto FCS005. Es importante continuar investigando esta molécula porque puede ser un potencial agente antiparkinsoniano.

Can therapeutic strategies prevent and manage dyskinesia in Parkinson's disease? An update.

Introduction: Dyskinesia is a motor complication of Parkinson's disease (PD) characterized by clinical heterogeneity and complex pathogenesis and associated with long-term levodopa therapy. Recent and controversial views on the management of PD patients have suggested that overall dyskinesia rates, and particularly troublesome dyskinesia, may be declining due to more conservative levodopa dosing regimens, widespread availability and early introduction of deep brain stimulation, and use of continuous drug delivery strategies. Nevertheless, anti-dyskinetic agents continue to be evaluated in clinical trials and recent efforts have focused on non-dopaminergic drugs.Areas covered: In this review, the authors discuss the clinical phenomenology and current understanding of dyskinesia in PD with a focus on up-to-date therapeutic strategies to prevent and manage these drug-related involuntary movements.Expert opinion: The way dyskinesia in PD is currently managed should be changed and attention should be focused toward a more personalized medicine rather than a one-fits-all-approach. The correct identification of dyskinesia types and tailored treatments are crucial for a better management of these involuntary movements together with a holistic approach which considers additional influencing factors. The future for dyskinesia treatment is likely to be found in non-dopaminergic approaches, first set into motion by the introduction of amantadine.

Coumarin analogue 3-methyl-7H-furo[3,2-g]chromen-7-one as a possible antiparkinsonian agent / El análogo de cumarina 3-metil-7H-furo[3,2-g]cromen-7-ona, un posible agente antiparkinsoniano

Abstract Introduction: Parkinson's disease is the second most common neurodegenerative disease. Monoamine oxidase B inhibitors are used in the treatment of this disease concomitantly with levodopa or as monotherapy. Several substituted coumarins have shown activity as inhibitors of monoamine oxidase B. Objective: To evaluate the possible antiparkinsonian effects of the coumarin analogue FCS005 (3-methyl-7H-furo[3,2-g]chromen-7-one) in mouse models, as well as its inhibitory activity towards monoamine oxidases (MAO) and its antioxidant activity. Materials and methods: FCS005 was synthesized and the reversal of hypokinesia was evaluated in the reserpine and levodopa models. Moreover, in the haloperidol model, its anticataleptic effects were evaluated. Additionally, the monoamine oxidase inhibitory activity and antioxidant activity of FCS005 were evaluated using in vitro and ex vivo studies, respectively. Results: FCS005 (100 mg/kg) caused the reversal of hypokinesia in the reserpine and levodopa models. This furocoumarin also presented anti-cataleptic effects at the same dose. Besides, it showed selective inhibitory activity towards the MAO-B isoform and antioxidant activity. Conclusion: These results attribute interesting properties to the compound FCS005. It is important to continue research on this molecule considering that it could be a potential antiparkinsonian agent.

Resumen Introducción. El segundo trastorno neurodegenerativo más común es la enfermedad de Parkinson. Los inhibidores de la monoamino oxidasa B se emplean en el tratamiento de esta enfermedad en monoterapia o concomitantemente con levodopa. Varios compuestos cumarínicos han mostrado actividad como inhibidores de la monoamino oxidasa B. Objetivo. Evaluar los posibles efectos antiparkinsonianos del análogo de la cumarina FCS005 (3-methyl-7H-furo [3,2-g ] chromen-7-one) en modelos de ratones, la actividad inhibitoria frente a las monoamino oxidasas (MAO) y la actividad antioxidante. Materiales y métodos. Se sintetizó la furanocumarina FCS005 y, en los modelos de reserpina y levodopa, se evaluó si producía reversión de la hipocinesia; en el modelo de haloperidol se evaluaron sus efectos anticatalépticos. Además, se evaluó in vitro la actividad inhibidora de MAO y, ex vivo, la actividad antioxidante del compuesto FCS005. Resultados. El compuesto FCS005 en dosis de 100 mg/kg produjo la remisión de la hipocinesia en los modelos de reserpina y de levodopa. Esta furanocumarina presentó efectos anticatalépticos con la misma dosis. Además, mostró tener actividad inhibitoria selectiva sobre la MAO B, así como efectos antioxidantes. Conclusión. Los resultados evidenciaron propiedades interesantes del compuesto FCS005. Es importante continuar investigando esta molécula porque puede ser un potencial agente antiparkinsoniano.

L-3-n-butylphthalide soft capsules in the treatment of Parkinson disease dementia: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: In recent years, L-3-n-butylphthalide (L-NBP) has been used for Parkinson disease dementia (PDD) to attenuate cognitive impairments in China. Therefore, we selected published and qualified clinical trials to conduct a systematic review and meta-analysis with the aim of assessing the effectiveness and safety of L-NBP in the treatment of PDD. OBJECTIVE: This systematic review and meta-analysis aimed to assess the effectiveness and safety of L-NBP in the treatment of PDD. METHODS: We searched PubMed, EMBASE, China National Knowledge Infrastructure, Chinese Scientific Journal Database (VIP database), and Wan-Fang Database to collect eligible articles. We calculated pooled estimates of odds ratios or the standard mean deviation with 95% confidence intervals. RESULTS: Eight randomized controlled trials were included in our meta-analysis. Our meta-analysis showed that L-NBP combined with Western medicine (WM) had a better effect on improving cognitive dysfunction, the total effective rate, symptoms of Parkinson disease (PD), and activities of daily living function than WM alone. Regarding safety, no serious adverse events were observed in the experimental group. CONCLUSION: We found that L-NBP as a complementary therapy may have a positive therapeutic effect for improving cognitive dysfunction, the total effective rate, symptoms of PD, quality of life, and the related serum factors in the treatment of PDD. Furthermore, L-NBP was a safe treatment for PDD. However, the findings of our meta-analysis may be influenced by the low quality of the included studies. We highlight the need to conduct trials with higher methodological quality.

Vector-mediated l-3,4-dihydroxyphenylalanine delivery reverses motor impairments in a primate model of Parkinson's disease.

Ever since its introduction 40 years ago l-3,4-dihydroxyphenylalanine (l-DOPA) therapy has retained its role as the leading standard medication for patients with Parkinson's disease. With time, however, the shortcomings of oral l-DOPA treatment have become apparent, particularly the motor fluctuations and troublesome dyskinetic side effects. These side effects, which are caused by the excessive swings in striatal dopamine caused by intermittent oral delivery, can be avoided by delivering l-DOPA in a more continuous manner. Local gene delivery of the l-DOPA synthesizing enzymes, tyrosine hydroxylase and guanosine-tri-phosphate-cyclohydrolase-1, offers a new approach to a more refined dopaminergic therapy where l-DOPA is delivered continuously at the site where it is needed i.e. the striatum. In this study we have explored the therapeutic efficacy of adeno-associated viral vector-mediated l-DOPA delivery to the putamen in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated rhesus monkeys, the standard non-human primate model of Parkinson's disease. Viral vector delivery of the two enzymes, tyrosine hydroxylase and guanosine-5'-tri-phosphate-cyclohydrolase-1, bilaterally into the dopamine-depleted putamen, induced a significant, dose-dependent improvement of motor behaviour up to a level identical to that obtained with the optimal dose of peripheral l-DOPA. Importantly, this improvement in motor function was obtained without any adverse dyskinetic effects. These results provide proof-of-principle for continuous vector-mediated l-DOPA synthesis as a novel therapeutic strategy for Parkinson's disease. The constant, local supply of l-DOPA obtained with this approach holds promise as an efficient one-time treatment that can provide long-lasting clinical improvement and at the same time prevent the appearance of motor fluctuations and dyskinetic side effects associated with standard oral dopaminergic medication.

Proposition of zinc supplementation during levodopa-carbidopa intestinal gel treatment.

OBJECTIVES: Levodopa-carbidopa intestinal gel (LCIG) infusion is a useful therapy for the wearing-off phenomenon of advanced Parkinson's disease (PD) patients. Recently, we found three PD patients that may have had a zinc deficiency after the LCIG infusion, possibly due to the zinc-chelating action of levodopa. This study aims to evaluate changes in serum zinc levels in three patients that received LCIG treatment and to determine possible remedies for zinc deficiency during treatment. MATERIALS AND METHODS: We performed a prospective blood analysis of serum zinc levels before, when possible, and after LCIG treatment in our three PD patients. RESULTS: The serum zinc levels of the first patient before treatment and 4 months after beginning LCIG treatment were 69 and 58 µg/dl, respectively. For the second patient, serum zinc levels before treatment and two months after starting LCIG treatment were 87 and 46 µg/dl, respectively. The baseline serum zinc level for the third patient was not examined, but was 48 µg/dl 5 months after starting the LCIG infusion. CONCLUSIONS: Levodopa-carbidopa intestinal gel infusion might have caused a zinc deficiency through levodopa zinc chelation. Zinc deficiency with LCIG infusion has not yet been reported, though preventing zinc deficiency may be an important factor in future LCIG treatment strategies.

DA-9701 on gastric motility in patients with Parkinson's disease: A randomized controlled trial.

INTRODUCTION: To evaluate the effect of DA-9701, a novel prokinetic drug, on gastric motility evaluated by magnetic resonance imaging in patients with Parkinson's disease (PD). METHODS: Forty PD patients were randomly allocated to receive either domperidone or DA-9701. Their gastric functions were evaluated using magnetic resonance imaging before and after 4-week treatment period. Information on levodopa daily dose, disease duration, and Unified PD Rating Scale scores was collected. In 18 patients (domperidone: 9, DA-9701: 9), plasma levodopa concentrations were determined. Primary outcome was assessed by a one-sided 95% confidence interval to show non-inferiority of DA-9701 vs. domperidone with a pre-determined non-inferiority margin of -10%. RESULTS: Thirty-eight participants (19 men and 19 women; mean age, 67.1 years) completed the study protocol (domperidone: DA-9701 = 19:19). Gastric emptying rate at 120 min (2-hr GER) was comparable between the 2 groups; it was not correlated with levodopa daily dose or disease duration or Unified PD Rating Scale scores (all p > 0.05). DA-9701 was not inferior to domperidone in changes of 2-hr GERs before and after the treatment (absolute difference, 4.0 %; one-sided 95% confidence interval, - 3.7 to infinity). However, a significant increase in 2-hr GER was observed only in DA-9701 group (54.5% and 61.8%, before and after treatment, respectively, p < 0.05). Plasma levodopa concentration showed an insignificant but increasing trend in DA-9701 group. There were neither adverse reactions nor deteriorations of parkinsonian symptoms observed in the study participants. CONCLUSION: DA-9701 can be used for the patients with PD to enhance gastric motility without aggravating PD symptoms (ClinicalTrials.gov number: NCT03022201).