A systematic review of the potential consequences of abnormal serum levels of vitamin B6 in people living with Parkinson's disease.

The prevalences of polyneuropathy and epilepsy are higher in people living with Parkinson's disease (PwPD) when compared to older adults. Vitamin B6 is widely available and affordable. PwPD are at higher risk of having abnormal serum levels of vitamin B6, which are associated with polyneuropathy and epilepsy that are potentially preventable and treatable. Potential contributors to abnormal B6 levels in PwPD include age, dietary habits, vitamin supplement misuse, gastrointestinal dysfunction and complex interactions with levodopa. The literature on the potential consequences of abnormal B6 levels in PwPD is limited by a small number of observational studies focused on polyneuropathy and epilepsy. Abnormal B6 levels have been reported in 60 of 145 PwPD (41.4% relative frequency). Low B6 levels were reported in 52 PwPD and high B6 levels were reported in 8 PwPD. There were 14 PwPD, polyneuropathy and low B6. There were 4 PwPD, polyneuropathy and high B6. There were 4 PwPD, epilepsy and low B6. Vitamin B6 level was low in 44.6% of PwPD receiving levodopa-carbidopa intestinal gel and in 30.1% of PwPD receiving oral levodopa-carbidopa. In almost all studies reporting low B6 in PwPD receiving oral levodopa-carbidopa, the dose of levodopa was ≥1000 mg/day. Rigorous epidemiological studies will clarify the prevalence, natural history and clinical relevance of abnormal serum levels of vitamin B6 in PwPD. These studies should account for diet, vitamin supplement use, gastrointestinal dysfunction, concurrent levels of vitamin B12, folate, homocysteine and methylmalonic acid, formulations and dosages of levodopa and other medications commonly used in PwPD.

Phytoconstituents of Datura metel extract improved motor coordination in haloperidol-induced cataleptic mice: Dual-target molecular docking and behavioural studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Parkinson's disease (PD) is a prominent health challenge characterized by complex aetiology and limited therapeutic breakthroughs. Datura metel (DM) is a medicinal plant containing active phytoconstituents with neuropharmacological potentials. In traditional medicine, it exerts anticholinergic, anti-inflammatory and antioxidant effects, and protection from organophosphate poisoning inclusively involved in the pharmacotherapy of PD. Its other PD-related medicinal potency includes treatment of motor sickness and bradycardia. However, the exact mechanisms of anti-PD effects of its phytoconstituents remain underexplored. MATERIALS AND METHODS: In this study, methanolic extract of DM was evaluated for anti-PD behavioural effects in vivo haloperidol-induced cataleptic mice. The GC-MS-identified phytochemicals were studied for one-drug-multi-target inhibitory mechanisms against some key targets for PD treatment, alpha-synuclein (ASN) and dopa decarboxylase (DDC) using molecular docking. RESULTS: and discussion: Chronic administration of 50, 100 and 200 mg/kg of DM extract improved the 14-s latency time induced by haloperidol to 54, 54 and 57 s respectively, whereas levodopa (30 mg/kg) produced 47 s in rotarod tests. Similarly, the descending times for haloperidol-induced cataleptic mice were significantly reduced from 110 s to 17.7, 17.7 and 12.5 s by the respective chronic doses of DM extract, whereas levodopa-administered mice spent 17.5 s descending the same 30 cm pole. The interesting motor coordination enhancements are suggestively due to synergistic inhibition of ASN and DCC by the phytoconstituents of DM, especially, atropine and scopolamine. From the docking analysis, the two phytochemicals interacted more potently with the active therapeutic sites of the dual targets than levodopa and carbidopa. CONCLUSION: Methanolic extract of DM contains active phytochemicals for multi-target-directed antiparkinsonian mechanisms amenable for further studies.

Tolcapone improves outcomes in patients with Parkinson disease treated by levodopa/carbidopa intestinal gel: A pilot study.

BACKGROUND: Patients with Parkinson disease (PD) treated with levodopa/carbidopa intestinal gel (LCIG) have higher prevalence of hyperhomocysteinemia and peripheral nerves damage. OBJECTIVE: The aim of our study was to test the effect of catechol-O-methyl transferase inhibitor tolcapone-as an add-on therapy to LCIG in patients with PD-on homocysteine (HCY) metabolism and nerve conduction study (NCS) parameters. METHODS: We evaluated NCS and serum B12, folic acid, and homocysteine in 16 patients with advanced PD on LCIG. Quality of life (QoL) was also assessed. Six subjects were treated with tolcapone add-on therapy (and LCIG dose reduction), 5 with B vitamin supplementation, and 5 without additional treatment. RESULTS: The level of HCY increased among patients without treatment (4.95 ± 12.54), and decreased in the vitamin (-17.73 ± 11.82) and tolcapone groups (-8.81 ± 8.36). Patients with tolcapone demonstrated improvement in polyneuropathic symptoms and signs compared with patients treated with vitamins or those without additional treatment (-0.83, d = 0.961). Although the most robust improvement in NCS parameters were observed with tolcapone, the findings were inconsistent to prove the effect of any intervention. Only tolcapone treatment was associated with improvement in QoL (d = 1.089). CONCLUSION: Our study indicates potential of tolcapone add-on therapy in LCIG treated patients in control of homocysteine levels, and improvement of polyneuropathic symptoms, as well as QoL.

Vitamin B6 Deficiency Anemia Attributed to Levodopa/Carbidopa Intestinal Gel Therapy for Parkinson's Disease: A Diagnostic Pitfall for Myelodysplastic Syndrome with Ring Sideroblasts.

Vitamin B6 (VB6) is essential to heme synthesis, and its deficiency can lead to anemia. VB6 deficiency anemia is typically microcytic, hypochromic, and sideroblastic. VB6 deficiency is a well-recognized complication of levodopa/carbidopa therapy, as metabolism of levodopa to dopamine is VB6-dependent, and carbidopa irreversibly forms bonds and deactivates VB6. We herein report a 75-year-old man with advanced Parkinson's disease who developed severe VB6 deficiency anemia due to levodopa/carbidopa intestinal gel therapy. His anemia was promptly resolved with simple oral supplementation of pyridoxal phosphate hydrate. VB6 deficiency anemia can mimic myelodysplastic syndrome and thus is an important differential diagnosis for patients administered levodopa/carbidopa.

Vitamins and Infusion of Levodopa-Carbidopa Intestinal Gel.

Levodopa-carbidopa intestinal gel infusion (LCIG) is an established therapy for advanced Parkinson disease (PD), resulting in a significant improvement of quality of life. With increased LCIG adoption worldwide, potential complications due to abnormal vitamin absorption or metabolism have been reported in these patients. Neurologists are unfamiliar with vitamins physiology and pathophysiological mechanisms in case of their deficiency. Unfortunately, clinical and laboratory guidelines related to vitamin monitoring and supplementation in the context of treatment with LCIG are not available. We herein summarize the current knowledge on three vitamins that are reduced with LCIG therapy reporting on their physiology, laboratory testing, and clinical impact of their deficiency/excess. In addition, we proposed an opinion-based recommendation for clinicians treating LCIG patients. Patients and caregivers should be informed about the risk of vitamin deficiency. Vitamin B12, homocysteine, and methylmalonic acid (MMA) should be tested before starting LCIG, six months after and once/year thereafter. Vitamin B6 and folate testing is not universally available but it should be considered if homocysteine is elevated but MMA and/or total vitamin B12 are normal. Prophylaxis of vitamin deficiency should be started as soon as LCIG is implemented, possibly even before. Dietary recommendations are enough in most patients although a subgroup of patients is at higher risk and should receive Vitamin B12 regularly and cycles of B6. Finally, once diagnosed a vitamin deficiency should be readily treated and accompanied by clinical and laboratory monitoring. Resistant cases should receive non-oral routes of administration and possibly discontinue LCIG, even temporarily.

Effect of catechin and commercial preparation of green tea essence on the pharmacokinetics of l-dopa in rabbits.

The aim of this study was to investigate drug interactions of L-dopa/carbidopa with catechin and green tea essence in rabbits following the simultaneous administration via an intramuscular injection of catechin or via an intragastric route for green tea essence with L-dopa/carbidopa. The results indicated that catechin at doses of 10, 20 and 50 mg/kg increased the area under the plasma concentration-time curve from time zero to the time of the last quantifiable concentration (AUC0-t ) of L-dopa by about 69, 78 and 42%, respectively. The metabolic ratios of the AUC0-t for 3-O-methyldopa (3-OMD)/L-dopa significantly decreased by about 56, 68 and 76% (P < 0.05), respectively. In addition, a single dose of 5/1.25 mg/kg L-dopa/carbidopa was co-administrated with 150 mg/kg green tea essence via an intragastric route with an oral-gastric tube. Comparing the related pharmacokinetic parameters of L-dopa, the clearance and metabolic ratio of L-dopa decreased by 20 and 19% (P < 0.05), respectively. In conclusion, catechin and green tea essence can significantly affect the metabolism of L-dopa by the catechol-O-methyltransferase (COMT) metabolic pathway. Catechin can enhance L-dopa bioavailability, and both catechin and green tea essence decreased 3-OMD formation. Therefore, catechin and green tea essence may increase L-dopa efficacy for Parkinson's disease treatment.

An Investigation of the Anti-Parkinsonism Potential of Co-enzyme Q10 and Co-enzyme Q10 /Levodopa-carbidopa Combination in Mice.

BACKGROUND: Despite decades of research, neurodegenerative disorders like Parkinson's disease remain a leading cause of disability worldwide, due to the insufficient reduction of disease burden by available medications. Recently, the benefits of dietary supplements like co-enzyme Q10 in neurodegenerative diseases have been reported. ; Aim: The protective effects of supplemental co-enzyme Q10 (CQ10) and possible additive benefits of CQ 10/Levodopa-Carbidopa (LD) in Chlorpromazine (CPZ)-induced Parkinsonism-like changes in mice were investigated. ; Methods: Male mice were assigned to ten groups of 30 mice each. Groups included: Vehicle control (fed Standard Diet (SD), and given intraperitoneal {ip} plus oral saline), LD group (fed SD, and given ip saline plus oral LD), two groups fed CQ10-supplemented diet (at 60 and 120 mg/kg of feed), and given ip plus oral saline, CPZ group (fed SD, and given ip CPZ plus oral saline), CPZ/LD group (fed SD, and given ip CPZ plus oral LD), two groups fed CQ10-supplemented diet (at 60 and 120 mg/kg of feed) and given ip CPZ plus oral saline, and another two groups fed CQ10-supplemented diet (at 60 and 120 mg/kg of feed) and given ip CPZ plus oral LD. The total duration of study was 21 days, and treatments were administered daily. Bodyweight and food intake were measured weekly, while neurobehavioural and biochemical tests were assessed at the end of the experimental period. ; Results: CQ10-supplementation was protective against CPZ-induced parkinsonism-like changes including, reduction in mortality, the reversal of retardation of open-field behaviours and reduction of catalepsy, increase in dopamine levels and decreased oxidative stress. CQ10 also showed significant improvements in these parameters when co-administered with LD. CQ10 (in groups administered CPZ/CQ10 60) showed greater benefit over LD on anxiety-related behaviours and also had additive benefits on working-memory. ; Conclusion: Dietary CQ10-supplementation was associated with demonstrable benefits in CPZinduced Parkinsonism-like changes in mice.

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.

Supplementary management with Pycnogenol® in Parkinson's disease to prevent cognitive impairment.

BACKGROUND: The aim of this registry study in patients with Parkinson's Disease (PD) in treatment, was to evaluate the effects of Pycnogenol® supplementation on some accessory symptoms and cognitive functions (COFU). METHODS: The registry included 43 PD patients who had been diagnosed at least one year before the start of the study. The PD condition was considered mild, with minimal progression. The management for these patients was a monotherapy using carbidopa/levodopa (standard management; SM). Supplementary Pycnogenol® was used at 150 mg/day for 4 weeks. The neurological management was not affected. RESULTS: Tolerability and safety were very good; the two registry groups were comparable with comparable symptoms at baseline. The most disabling symptoms were considered tremor, bradychinesia, alterations in COFU, rigidity and speech changes. All symptoms were rated as mild-to-moderate. After 4 weeks, these target symptoms were significantly attenuated with the supplement in comparison with the SM only (P<0.05). Particularly the COFU score was significantly higher (P<0.05) with the supplement. No interference between the main neurological management and the supplement was observed. Oxidative stress (plasma free radicals), high in both registry groups at inclusion, was significantly lower in the supplement group at 4 weeks (P<0.05). The main PD-associated items (cognitive aspects, motory and postural aspects) considered the most common and disturbing problems were evaluated and scored (0 to 4) with a visual scale line. At 4 weeks, the scores for all items were lower in the supplement group in comparison with the control, SM group. Peripheral edema was present in all patients at inclusion. The edema was minimal at inclusion (at the ankle-foot level with pretibial extension) and present in all subjects. It changed in two SM subjects and was still present at 4 weeks in 19 out 22 of the SM patients. In the supplemented patients, edema (present at inclusion in all subjects), was visible in 4 subjects out of 21 (19%) at 4 weeks. CONCLUSIONS: Pycnogenol® supplementation may help in selected patients with PD - under stable neurological treatment - to improve some signs and symptoms and some aspects associated with COFU. Studies are in progress on a larger population sample and with new evaluation methods.

An Evaluation of the Effects of Pyridoxal Phosphate in Chlorpromazineinduced Parkinsonism using Mice.

BACKGROUND: Parkinsonism is a neurodegenerative disorder with a heavy disease burden, despite the discovery and application of drugs. Current research is beginning to suggest the possible crucial roles of micronutrients such as pyridoxal phosphate in the prevention or management of neurodegenerative disorders. OBJECTIVE: We investigated the possible protective effects of supplemental pyridoxal phosphate in Chlorpromazine (CPZ)-induced Parkinsonism-like changes in mice. METHODS: Mice were assigned to eight groups of 30 mice each. Groups included Vehicle control (fed standard diet (SD), and administered intraperitoneal {ip} injection of saline and saline per orem), levodopa-carbidopa (LD) group (SD, saline ip and LD per orem), two groups fed pyridoxal phosphate-supplemented diet (at 100 and 200 mg/kg of feed), and administered saline both ip and orally, CPZ group (SD, CPZ ip and saline per orem), CPZ/LD group (SD, CPZ ip and LD per orem) and finally two groups fed pyridoxal phosphate -supplemented diet (at 100 and 200 mg/kg of feed) and administered CPZ ip plus saline per orem. Treatments were administered daily for a period of 21 days to allow for the induction of Parkinsonism features. Body weight and food intake were measured weekly while neurobehavioural and biochemical tests were assessed at the end of the experimental period. RESULTS: Pyridoxal phosphate supplementation was associated with a reduction in CPZ-induced suppression of open-field horizontal locomotion and rearing; and a significant increase in grooming activity. Administration of pyridoxal phosphate-supplemented diet was also associated with improvements in working-memory in CPZ-treated mice; and there was reduction in the index of anxiety and catalepsy score. CONCLUSION: Pyridoxal phosphate supplementation was associated with significant benefits in CPZ-induced Parkinsonism-like changes in mice.

Neurochemical supplementation in patients with depressed levels of participation after brain tumor surgery: Rationale and preliminary results.

A unique challenge in some brain tumor patients is the fact that tumors arising in certain areas of the brain involve the neural structures of consciousness or alertness, limiting the patient's ability to participate in rehabilitation following surgery. A critical question is whether neurostimulant therapy can help patients participate in rehabilitation efforts. We performed a retrospective review of all patients undergoing brain tumor surgery by the senior author from 2012 to 2018. We limited this study to patients with tumors occupying critical structures related to consciousness, alertness, and motor initiation. A combination of methylphenidate and levodopa/carbidopa was used to monitor the progress of patients through neurorehabilitation efforts. We identified 101 patients who experienced an inability to participate in rehabilitation (ITPR) in the post-operative period. Of these, 86 patients (85%) were treated with methylphenidate and levodopa/carbidopa. Cases of ITPR were related to dysfunction of the brainstem (12/86 cases, 14%), thalamus (17/86 cases, 20%), hypothalamus (14/86 cases, 16%), basal ganglia (13/86 cases, 15%), and medial frontal lobe (30/86 cases, 35%). Of the 86 individuals treated, 47/86 patients (55%) showed early improvement in their ability to participate with rehabilitation. At three month follow-up, 58/86 patients (67%) had returned to living independently or were at least interactive and cooperative during follow-up examination. This feasibility report suggests that combined therapy with methylphenidate and levodopa/carbidopa may help patients participate in neurorehabilitation efforts in the immediate post-operative period following brain tumor surgery. Randomized, controlled clinical trials are needed to explore this concept more thoroughly.

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.

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.

Mucuna Pruriens Combined with Carbidopa in Parkinson's Disease: A Case Report.

We present a 48-year-old woman with Parkinson's disease in whom carbidopa was added to Mucuna pruriens, resulting in marked motor improvement (documented on video and using MDS-UPDRS motor scores). This case report shows that adding a dopa-decarboxylase inhibitor (DDCI) to Mucuna pruriens could fit well in a personalized approach for patients who are reluctant to start levodopa. Meanwhile, larger trials with a longer follow-up are needed to establish the true effects and tolerability of Mucuna pruriens plus a DDCI.

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.

New advances in amblyopia therapy I: binocular therapies and pharmacologic augmentation.

Amblyopia therapy options have traditionally been limited to penalisation of the non-amblyopic eye with either patching or pharmaceutical penalisation. Solid evidence, mostly from the Pediatric Eye Disease Investigator Group, has validated both number of hours a day of patching and days per week of atropine use. The use of glasses alone has also been established as a good first-line therapy for both anisometropic and strabismic amblyopia. Unfortunately, visual acuity equalisation or even improvement is not always attainable with these methods. Additionally, non-compliance with prescribed therapies contributes to treatment failures, with data supporting difficulty adhering to full treatment sessions. Interest in alternative therapies for amblyopia treatment has long been a topic of interest among researchers and clinicians alike. Incorporating new technology with an understanding of the biological basis of amblyopia has led to enthusiasm for binocular treatment of amblyopia. Early work on perceptual learning as well as more recent enthusiasm for iPad-based dichoptic training have each generated interesting and promising data for vision improvement in amblyopes. Use of pharmaceutical augmentation of traditional therapies has also been investigated. Several different drugs with unique mechanisms of action are thought to be able to neurosensitise the brain and enhance responsiveness to amblyopia therapy. No new treatment has emerged from currently available evidence as superior to the traditional therapies in common practice today. But ongoing investigation into the use of both new technology and the understanding of the neural basis of amblyopia promises alternate or perhaps better cures in the future.

Daily intake of Mucuna pruriens in advanced Parkinson's disease: A 16-week, noninferiority, randomized, crossover, pilot study.

BACKGROUND: Thousands of individuals with Parkinson's disease (PD) in low-income countries have limited access to marketed levodopa preparations. Mucuna pruriens (MP), a levodopa-containing leguminous plant growing in tropical areas, may be a sustainable alternative therapy for indigent patients. Single-dose intake of MP proved noninferior to marketed levodopa preparations. METHODS: Fourteen PD patients with motor fluctuations and dyskinesias received MP powder (obtained from roasted seeds) and marketed levodopa/carbidopa (LD/CD) in a randomized order and crossover design over a 16-week period. Efficacy measures were changes in quality of life, motor and non-motor symptoms, and time with good mobility without troublesome dyskinesias. Safety measures included tolerability, frequency of adverse events, changes in laboratory indices and electrocardiogram. RESULTS: Daily intake of MP was associated with a variable clinical response, especially in terms of tolerability. Seven patients (50%) discontinued MP prematurely due to either gastrointestinal side-effects (n = 4) or progressive worsening of motor performance (n = 3), while nobody discontinued during the LD/CD phase. In those who tolerated MP, clinical response to MP was similar to LD/CD on all efficacy outcome measures. Patients who dropped out entered a study extension using MP supernatant water (median[IQR], 16 [7-20] weeks), which was well tolerated. CONCLUSIONS: The overall benefit provided by MP on the clinical outcome was limited by tolerability issues, as one could expect by the relatively rapid switch from LD/CD to levodopa alone in advanced PD. Larger parallel-group studies are needed to identify appropriate MP formulation (e.g. supernatant water), titration scheme and maintenance dose to minimize side-effects in the long-term. CLINICAL TRIALS. GOV IDENTIFIER: NCT02680977.

Dopaminergic tone does not influence pain levels during placebo interventions in patients with chronic neuropathic pain.

Placebo effects have been reported in patients with chronic neuropathic pain. Expected pain levels and positive emotions are involved in the observed pain relief, but the underlying neurobiology is largely unknown. Patients with neuropathic pain are highly motivated for pain relief, and as motivational factors such as expectations of reward, as well as pain processing in itself, are related to the dopaminergic system, it can be speculated that dopamine release contributes to placebo effects in neuropathic pain. Nineteen patients with neuropathic pain after thoracic surgery were tested during a placebo intervention consisting of open and hidden applications of the pain-relieving agent lidocaine (2 mL) and no treatment. The dopamine antagonist haloperidol (2 mg) and the agonist levodopa/carbidopa (100/25 mg) were administered to test the involvement of dopamine. Expected pain levels, desire for pain relief, and ongoing and evoked pain were assessed on mechanical visual analog scales (0-10). Significant placebo effects on ongoing (P ≤ 0.003) and evoked (P ≤ 0.002) pain were observed. Expectancy and desire accounted for up to 41.2% and 71.5% of the variance in ongoing and evoked pain, respectively, after the open application of lidocaine. We found no evidence for an effect of haloperidol and levodopa/carbidopa on neuropathic pain levels (P = 0.071-0.963). Dopamine seemed to influence the levels of expectancy and desire, yet there was no evidence for indirect or interaction effects on the placebo effect. This is the first study to suggest that dopamine does not contribute to placebo effects in chronic neuropathic pain.

Initiation of Levodopa-Carbidopa Intestinal Gel Infusion Using Telemedicine (Video Communication System) Facilitates Efficient and Well-Accepted Home Titration in Patients with Advanced Parkinson's Disease.

BACKGROUND: Levodopa-carbidopa intestinal gel (LCIG; Duodopa®) is used for continuous infusion in advanced Parkinson's disease. To achieve optimal effect, the LCIG dose is individually titrated, traditionally conducted during hospitalization in Sweden. However, dose adjustment depends on surrounding conditions, physical activity, and emotional stress, which is why titration at home could be beneficial. Telemedicine (TM) using a video communication system offers alternative titration procedures, allowing LCIG initiation at home. OBJECTIVE: Study objectives were to show the feasibility of TM for LCIG home titration, evaluate resource use, and assess patient, neurologist, and nurse satisfaction. METHODS: Four clinics enrolled 15 patients to observe efficiency and feasibility of TM-based monitoring. RESULTS: Patient median (range) age was 67 (52-73) years and time since diagnosis was 10 (7-23) years. Median time between LCIG initiation and end of TM-assisted titration was 2.8 (2.0-13.8) days. Median time required for home titration by neurologists, nurses, and patients was (hours:minutes) 1 : 14 (0 : 29-1 : 52), 5 : 49 (2 : 46-10 : 3), and 8 : 53 (4 : 11-14 : 11), respectively. Neurologists and nurses considered this to be less time than required for hospital titration. TM allowed patients 92% free time from start to end of titration. Technical problems associated with TM contacts were rare, mostly related to digital link, and quickly resolved. Patients, neurologists, and nurses were satisfied using TM. No serious adverse events were reported; there was one device complaint (tube occlusion). CONCLUSIONS: In this study, TM-assisted LCIG titration at home was resource-efficient, technically feasible, well-accepted and was deemed satisfactory by patients, neurologists, and nurses.