A review of ropinirole prolonged release in Parkinson's disease

3D Printed Drug Delivery Systems in Action-Magnetic Resonance Imaging and Relaxometry for Monitoring Mass Transport Phenomena

The hypothesis of the study was that (1) 3D printed drug delivery systems (DDS) could be characterized in situ during drug release using NMR/MRI techniques in terms of mass transport phenomena description (interfacial phenomena), particularly for systems dealing with two mobile phases (e.g., water and low molecular weight liquid polymer); (2) consequently, it could be possible to deduce how these interfacial mass transport phenomena influence functional properties of 3D printed DDS. Matrix drug delivery systems, prepared using masked stereolithography (MSLA), containing poly(ethylene glycol) diacrylate (PEGDA) and low molecular weight polyethylene glycol (PEG) with ropinirole hydrochloride (RH) were studied as example formulations. The PEGDA to PEG (mobile phase) concentration ratio influenced drug release. It was reflected in spatiotemporal changes in parametric T2 relaxation time (T2) and amplitude (A) images obtained using magnetic resonance imaging (MRI) and T1-T2 relaxation time correlations obtained using low-field time-domain nuclear magnetic resonance (LF TD NMR) relaxometry during incubation in water. For most of the tested formulations, two signal components related to PEG and water were assessed in the hydrated matrices by MRI relaxometry (parametric T2/A images). The PEG component faded out due to outward PEG diffusion and was gradually replaced by the water component. Both components spatially and temporally changed their parameters, reflecting evolving water-polymer interactions. The study shows that dynamic phenomena related to bidirectional mass transport can be quantified in situ using NMR and MRI techniques to gain insight into drug release mechanisms from 3D printed DDS systems.

G protein-coupled receptors in neurodegenerative diseases and psychiatric disorders

Neuropsychiatric disorders are multifactorial disorders with diverse aetiological factors. Identifying treatment targets is challenging because the diseases are resulting from heterogeneous biological, genetic, and environmental factors. Nevertheless, the increasing understanding of G protein-coupled receptor (GPCR) opens a new possibility in drug discovery. Harnessing our knowledge of molecular mechanisms and structural information of GPCRs will be advantageous for developing effective drugs. This review provides an overview of the role of GPCRs in various neurodegenerative and psychiatric diseases. Besides, we highlight the emerging opportunities of novel GPCR targets and address recent progress in GPCR drug development.

D2/3 Agonist during Learning Potentiates Cued Risky Choice

Impulse control and/or gambling disorders can be triggered by dopamine agonist therapies used to treat Parkinson's disease, but the cognitive and neurobiological mechanisms underlying these adverse effects are unknown. Recent data show that adding win-paired sound and light cues to the rat gambling task (rGT) potentiates risky decision-making and impulsivity via the dopamine system, and that changing dopaminergic tone has a greater influence on behavior while subjects are learning task contingencies. Dopamine agonist therapy may therefore be potentiating risk-taking by amplifying the behavioral impact of gambling-related cues on novel behavior. Here, we show that ropinirole treatment in male rats transiently increased motor impulsivity but robustly and progressively increased choice of the high-risk/high-reward options when administered during acquisition of the cued but not uncued rGT. Early in training, ropinirole increased win-stay behavior after large unlikely wins on the cued rGT, indicative of enhanced model-free learning, which mediated the drug's effect on later risk preference. Ex vivo cFos imaging showed that both chronic ropinirole and the addition of win-paired cues suppressed the activity of dopaminergic midbrain neurons. The ratio of midbrain:prefrontal cFos+ neurons was lower in animals with suboptimal choice patterns and tended to predict risk preference across all rats. Network analyses further suggested that ropinirole induced decoupling of the dopaminergic cells of the VTA and nucleus accumbens but only when win-paired cues were present. Frontostriatal activity uninformed by the endogenous dopaminergic teaching signal therefore appeared to perpetuate risky choice, and ropinirole exaggerated this disconnect in synergy with reward-paired cues.SIGNIFICANCE STATEMENT D2/3 receptor agonists, used to treat Parkinson's disease, can cause gambling disorder through an unknown mechanism. Ropinirole increased risky decision-making in rats, but only when wins were paired with casino-inspired sounds and lights. This was mediated by increased win-stay behavior after large unlikely wins early in learning, indicating enhanced model-free learning. cFos imaging showed that ropinirole suppressed activity of midbrain dopamine neurons, an effect that was mimicked by the addition of win-paired cues. The degree of risky choice rats exhibited was uniquely predicted by the ratio of midbrain dopamine:PFC activity. Depriving the PFC of the endogenous dopaminergic teaching signal may therefore drive risky decision-making on-task, and ropinirole acts synergistically with win-paired cues to amplify this.

The effect and safety of ropinirole in the treatment of Parkinson disease: A systematic review and meta-analysis

BACKGROUND

It is necessary to conduct a meta-analysis of the clinical randomized controlled trials (RCTs) on ropinirole in the treatment of Parkinson disease (PD), to explore the effects and safety of ropinirole, and to provide a theoretical basis for clinically safe and rational drug use.

METHODS

RCTs on the effectiveness and safety of ropinirole in the treatment of PD were searched. We searched Dutch medical literature database, Pubmed, Cochrane Library, China National Knowledge Infrastructure, Wanfang Knowledge Service Platform up to December 15, 2020. The Cochrane risk bias assessment tool was used to evaluate the quality of the included literature, and the RevMan5.3 software was used for meta-analysis.

RESULTS

A total of 12 RCTs with 3341 patients were included. The changes of Parkinson Disease Rating Scale Part II score (mean difference = -2.23, 95% confidence interval [CI] -2.82 to -1.64) and Parkinson Disease Rating Scale Part III scores (mean difference = -4.93, 95%CI -5.25 to -4.61) in the ropinirole group was significantly lower than that in the control group. The incidence of dizziness (odd risk [OR] = 1.85, 95%CI 1.50-2.28), nausea (OR = 2.17, 95%CI 1.81-2.59), vomiting (OR = 2.73, 95%CI 1.47-5.09), and lethargy (OR = 2.19, 95%CI 1.39-3.44) in the ropinirole group was significantly higher than that in the control group (all P < .05), and there were no significant differences in the incidence of headache (OR = 1.14, 95%CI 0.79-1.65) and insomnia (OR = 1.06, 95%CI 0.72-1.55) were found between 2 groups (all P > .05).

CONCLUSIONS

Ropinirole can help improve the ability of daily living and exercise function of PD patients, but it will increase the incidence of related adverse reactions, which needs to be further confirmed by subsequent large-scale, high-quality RCTs.

Neuroprotective Effect of Astersaponin I against Parkinson's Disease through Autophagy Induction

An active compound, triterpene saponin, astersaponin I (AKNS-2) was isolated from Aster koraiensis Nakai (AKNS) and the autophagy activation and neuroprotective effect was investigated on in vitro and in vivo Parkinson's disease (PD) models. The autophagy-regulating effect of AKNS-2 was monitored by analyzing the expression of autophagy-related protein markers in SHSY5Y cells using Western blot and fluorescent protein quenching assays. The neuroprotection of AKNS-2 was tested by using a 1-methyl-4-phenyl-2,3-dihydropyridium ion (MPP⁺)-induced in vitro PD model in SH-SY5Y cells and an MPTP-induced in vivo PD model in mice. The compound-treated SH-SY5Y cells not only showed enhanced microtubule-associated protein 1A/1B-light chain 3-II (LC3-II) and decreased sequestosome 1 (p62) expression but also showed increased phosphorylated extracellular signal-regulated kinases (p-Erk), phosphorylated AMP-activated protein kinase (p-AMPK) and phosphorylated unc-51-like kinase (p-ULK) and decreased phosphorylated mammalian target of rapamycin (p-mTOR) expression. AKNS-2-activated autophagy could be inhibited by the Erk inhibitor U0126 and by AMPK siRNA. In the MPP⁺-induced in vitro PD model, AKNS-2 reversed the reduced cell viability and tyrosine hydroxylase (TH) levels and reduced the induced α-synuclein level. In an MPTP-induced in vivo PD model, AKNS-2 improved mice behavioral performance, and it restored dopamine synthesis and TH and α-synuclein expression in mouse brain tissues. Consistently, AKNS-2 also modulated the expressions of autophagy related markers in mouse brain tissue. Thus, AKNS-2 upregulates autophagy by activating the Erk/mTOR and AMPK/mTOR pathways. AKNS-2 exerts its neuroprotective effect through autophagy activation and may serve as a potential candidate for PD therapy.

Neuronal Dopamine D3 Receptors: Translational Implications for Preclinical Research and CNS Disorders

Dopamine (DA), as one of the major neurotransmitters in the central nervous system (CNS) and periphery, exerts its actions through five types of receptors which belong to two major subfamilies such as D1-like (i.e., D1 and D5 receptors) and D2-like (i.e., D2, D3 and D4) receptors. Dopamine D3 receptor (D3R) was cloned 30 years ago, and its distribution in the CNS and in the periphery, molecular structure, cellular signaling mechanisms have been largely explored. Involvement of D3Rs has been recognized in several CNS functions such as movement control, cognition, learning, reward, emotional regulation and social behavior. D3Rs have become a promising target of drug research and great efforts have been made to obtain high affinity ligands (selective agonists, partial agonists and antagonists) in order to elucidate D3R functions. There has been a strong drive behind the efforts to find drug-like compounds with high affinity and selectivity and various functionality for D3Rs in the hope that they would have potential treatment options in CNS diseases such as schizophrenia, drug abuse, Parkinson’s disease, depression, and restless leg syndrome. In this review, we provide an overview and update of the major aspects of research related to D3Rs: distribution in the CNS and periphery, signaling and molecular properties, the status of ligands available for D3R research (agonists, antagonists and partial agonists), behavioral functions of D3Rs, the role in neural networks, and we provide a summary on how the D3R-related drug research has been translated to human therapy.

Amorphous Ropinirole-Loaded Mucoadhesive Buccal Film: A Potential Patient-Friendly Tool to Improve Drug Pharmacokinetic Profile and Effectiveness

Nowadays the therapeutic strategies to manage Parkinson’s Disease are merely symptomatic and consist of administering L-DOPA and/or dopamine receptor agonists. Among these, Ropinirole (ROP) is a widely orally-administered molecule, although it is extensively susceptible to hepatic metabolism. Since literature reports the buccal mucosa as a potentially useful route to ROP administration, the development of novel, effective, and comfortable oromucosal formulations should prove desirable in order to both enhance the therapeutic efficacy of the drug and allow a personalized therapeutic strategy able to meet the patient’s needs. The results of the proposed ROP film as a new dosage form show that it is flexible; uniform; and characterized by suitable surface pH; good mucoadhesiveness; low swelling degree; and fast, complete drug release. Moreover, after ex vivo evaluation on a film having an area of 0.282 cm² and dose of 2.29 mg, the results of drug flux through the buccal mucosa are closely comparable to the amount of ROP that reaches the bloodstream at the steady-state condition after ROP-PR 4 mg oral administration, calculated according to the literature (0.237 mg/cm²·h⁻¹ vs. 0.243 mg/h, respectively). Moreover, drug flux and ROP dose could be accurately modulated time-by-time depending on the patient’s need, by varying the administered disk area. In addition, the proposed ROP film displays no lag time, producing an immediate drug input in the bloodstream, which could result in a prompt therapeutic response. These findings make ROP film a potentially comfortable and patient-friendly formulation, and a promising candidate for further clinical trials.

Pharmacological Treatment of Early Motor Manifestations of Parkinson Disease (PD)

Parkinson disease (PD), as a slowly progressive neurodegenerative disorder, undergoes six neuropathological stages. The earliest clinical manifestation presents in the middle stage of the disorder pathologically, when 50% or more of the dopaminergic neurons have degenerated in the substantia nigra. This discrepancy between the early stage clinically and that pathologically has, in part, spurred the debate as to when it is best to initiate symptomatic therapy. The most well-studied monotherapeutic agents for PD in its early course include levodopa (the cornerstone of PD therapy), dopamine agonists, and monoamine oxidase inhibitors (MAOIs). With several options for initiating pharmacologic therapy, along with the heterogenous presentation of the disorder, an individualized approach is warranted. Careful deliberation must be done to optimize risk reduction while providing effective symptom control, taking the chronological age, comorbidities, social and financial disposition, work status, and both immediate- and long-term goals into consideration. Generally, treatment can be delayed in patients with mild symptoms and minimal functional impairment at any age. If treatment must be initiated, dopamine agonists and monoamine oxidase type B inhibitors can be used, especially in younger patients with milder disease. However, for older patients, those with moderate to severe PD symptoms, regardless of age, or for patients with greater comorbidities, levodopa generally remains the better choice. Eventually, regardless of initial therapy, studies have shown that most will eventually require levodopa therapy when symptoms become more disabling.

Neuroprotective Effect of Ropinirole Lipid Nanoparticles Enriched Hydrogel for Parkinson's Disease: In Vitro, Ex Vivo, Pharmacokinetic and Pharmacodynamic Evaluation

Parkinson’s disease (rp) is a progressive neurodegenerative disorder. Ropinirole (RP) is a newer generation dopamine agonist used for the treatment of PD. It is prescribed as oral dosage form. However, limited oral bioavailability and frequent dosing limits the RP usage. The objective of the current investigation was to develop, optimize, evaluate pharmacokinetic (PK) and pharmacodynamic (PCD) activity of RP loaded solid lipid nanoparticles (RP-SLNs) and nanostructured lipid carriers (RP-NLCs) and containing hydrogel (RP-SLN-C and RP-NLC-C) formulations for improved oral and topical delivery. RP loaded lipid nanoparticles were optimized and converted to hydrogel using carbopol 934 as the gelling polymer. PK and PCD studies in haloperidol-induced PD were conducted in male Wistar rats. In vitro and ex vivo permeation studies showed sustained release profile and enhanced permeation compared with control formulations. Differential scanning calorimeter and X-ray diffraction studies revealed amorphous transformation; scanning electron microscope showed the spherical shape of RP in lipid nanoparticles. PK studies showed 2.1 and 2.7-folds enhancement from RP-SLN and RP-NLC from oral administration, 3.0 and 3.3-folds enhancement from RP-SLN-C and RP-NLC-C topical administration, compared with control formulations, respectively. RP-SLN-C and RP-NLC-C showed 1.4 and 1.2-folds topical bioavailability enhancement compared with RP-SLN and RP-NLC oral administration, respectively. PCD studies showed enhanced dopamine, glutathione, catalase levels and reduced lipid peroxidation levels, compared with the haloperidol-induced PD model. Overall, the results demonstrated that lipid nanoparticles and corresponding hydrogel formulations can be considered as an alternative delivery approach for the improved oral and topical delivery of RP for the effective treatment of PD.

Chronic administration of the dopamine D2/3 agonist ropinirole invigorates performance of a rodent slot machine task, potentially indicative of less distractible or compulsive-like gambling behaviour

RATIONALE

Whilst dopamine agonist therapies can successfully manage the symptoms of diseases such as Parkinson's disease (PD), fibromyalgia and restless leg syndrome, they can also cause impulse control and addiction disorders such as gambling disorder (GD). These compulsive behaviours seriously undermine the utility of such treatments.

OBJECTIVES

The objective of the study was to model this phenomenon using a rodent slot machine task (rSMT) in order to investigate the neurobiological basis underlying such behavioural changes.

METHODS

Male Long Evans rats were trained to perform the rSMT. The D₂-like agonist ropinirole, or saline, was then delivered continuously for 28 days via osmotic mini-pump. The effects of ropinirole on baseline rSMT performance, as well as extinction and reinstatement sessions, were determined during this time. Brain samples from key frontostriatal regions implicated in GD and PD were then harvested immediately or after a 4-week washout period during which behaviour returned to pre-drug baseline.

RESULTS

Ropinirole invigorated task performance, in that drug treatment resulted in a robust and sustained increase in the number of trials completed. Ex vivo analyses revealed that chronic ropinirole treatment led to a pattern of changes indicative of upregulation within the β-arrestin-AKT-GSK3β intracellular cascade, recently theorised to dominate D₂-mediated signalling under hyperdopaminergic conditions, in the dorsal striatum, rather than the canonical PKA-dependent signalling pathway associated with D₂ receptor activation.

CONCLUSIONS

Such findings provide novel insight into the role of dopamine signalling in mediating compulsive-like gambling behaviour and may inform more directed pharmacotherapies for the treatment of both idiopathic and iatrogenic GD.

cAMP response element binding protein phosphorylation in nucleus accumbens underlies sustained recovery of sensorimotor gating following repeated D₂-like receptor agonist treatment in rats

BACKGROUND

Prepulse inhibition (PPI) is a cross-species measure of sensorimotor gating. PPI deficits are observed in humans and rats upon acute treatment with dopamine D₂-like receptor agonists and in patients with schizophrenia. Repeated treatment with a D₂-like agonist, however, reverses PPI deficits and increases cyclic adenosine monophosphate (cAMP) signaling in the nucleus accumbens (NAc). This study examined the short- and long-term effects on PPI of treatment with quinpirole and ropinirole, dopamine D₂/D₃ receptor agonists, and the molecular mechanism by which they occur.

METHODS

PPI was assessed in adult male Sprague-Dawley rats following acute and chronic treatment with quinpirole or ropinirole and 1, 2, 3, and 4 weeks after termination of repeated ropinirole treatment. Finally, the effect of dominant negative mutant cAMP response element binding protein (CREB) overexpression in the NAc on PPI following chronic quinpirole treatment was assessed.

RESULTS

Acute quinpirole produced dose-dependent PPI deficits, whereas ropinirole caused consistent PPI reduction at all but the highest dose. Repeated ropinirole treatment significantly increased PPI compared with acute treatment, and increased CREB phosphorylation in NAc neurons. Subsequent ropinirole challenge had no effect as long as 28 days later, at which time NAc CREB phosphorylation had normalized. Overexpression of dominant negative mutant CREB prevented PPI recovery induced by chronic quinpirole treatment.

CONCLUSIONS

Chronic quinpirole or ropinirole treatment produces sustained PPI recovery; CREB activity in the NAc is required to induce PPI recovery but not to maintain it. The results suggest that transcriptional regulation by CREB mediates long-lasting changes occurring within NAc circuits to promote recovery of sensorimotor gating.

Treatment strategies for Parkinson's disease

Parkinson's disease (PD) is caused by progressive degeneration of dopamine (DA) neurons in the substantia nigra pars compacta (SNpc), resulting in the deficiency of DA in the striatum. Thus, symptoms are developed, such as akinesia, rigidity and tremor. The aetiology of neuronal death in PD still remains unclear. Several possible mechanisms of the degeneration of dopaminergic neurons are still elusive. Various mechanisms of neuronal degeneration in PD have been proposed, including formation of free radicals, oxidative stress, mitochondrial dysfunction, excitotoxicity, calcium cytotoxicity, trophic factor deficiency, inflammatory processes, genetic factors, environmental factors, toxic action of nitric oxide, and apoptosis. All these factors interact with each other, inducing a vicious cycle of toxicity causing neuronal dysfunction, atrophy and finally cell death. Considerable evidence suggests that free radicals and oxidative stress may play key roles in the pathogenesis of PD. However, currently, drug therapy cannot completely cure the disease. DA replacement therapy with levodopa (L-Dopa), although still being a gold standard for symptomatic treatment of PD, only alleviates the clinical symptoms. Furthermore, patients usually experience severe side effects several years after the L-Dopa treatment. Until now, no therapy is available to stop or at least slow down the neurodegeneration in patients. Therefore, efforts are made not only to improve the effect of L-Dopa treatment for PD, but also to investigate new drugs with both antiparkinsonian and neuroprotective effects. Here, the advantages and limitations of current and future therapies for PD were dicussed. Current therapies include dopaminergic therapy, DA agonists, MAO-B inhibitor, COMT inhibitors, anticholinergic drugs, surgical procedures such as pallidotomy and more specifically deep brain stimulation of the globus pallidus pars interna (GPi) or subthalamic nucleus (STN), and stem cell transplantation.