Novel drug delivery systems of β2 adrenoreceptor agonists to suppress SNCA gene expression and mitochondrial oxidative stress in Parkinson’s disease management

Identification and Validation of Oxidative Stress-Related Hub Genes in Parkinson's Disease

Accumulating evidence suggests that oxidative stress plays a crucial role in the pathogenesis of Parkinson's disease (PD). The aims of this study were to identify oxidative stress-related hub genes, validate them through the construction of a diagnostic model, explore their interactions with miRNAs and transcription factors (TFs) and predict potential drug targets. Differentially expressed genes (DEGs) in the substantia nigra of PD patients were identified by analyzing a combination of datasets selected from the GEO database, including GSE7621, GSE20141, GSE49036, and GSE20163. The candidate genes associated with oxidative stress were screened by determining the overlap among the DEGs, oxidative stress-related genes (OSGs) and genes in key modules with the highest cor values identified via weighted gene coexpression network analysis (WGCNA). The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to perform functional enrichment analysis of these candidate genes. The hub genes were identified via protein-protein interaction (PPI) analysis, and receiver operating characteristic (ROC) curves were constructed to assess the diagnostic value of each hub gene. Then, a diagnostic model was constructed via least absolute shrinkage and selection operator (LASSO) regression with the hub genes identified above, and the model was further validated in external validation datasets (GSE20292 and GSE20164). Gene-miRNA and gene-TF regulatory networks were predicted via the miRNet database, whereas candidate drugs were predicted via the Drug-Gene Interaction database. After analysis of the intersection of the 7975 DEGs, 434 OSGs, and 3582 genes identified through WGCNA, 76 candidate genes were identified. A total of 9 hub genes (JUN, KEAP1, SRC, GPX5, MMP9, TXN, MAPK3, GPX2, and IL1A) were identified via PPI and ROC curve analyses. A diagnostic model with the ability to reliably predict PD on the basis of the identified hub genes (AUC = 0.925) was constructed. Further analysis of these 9 genes revealed 64 targeted miRNAs, 35 TFs in regulatory networks and 86 potential therapeutic agents. Nine hub genes related to oxidative stress in the pathogenesis of PD were identified. These genes show strong diagnostic performance and could serve as therapeutic targets. These findings might facilitate the development of promising candidate biomarkers and potential disease-modifying therapies for PD.

Recent Advances in Marine-Derived Nanoformulation for the Management of Glioblastoma

Glioma is the most common and aggressive type of central nervous system tumor as categorized by the World Health Organization. Glioblastoma (GBA), in general, exhibits a grim prognosis and short life expectancy, rarely exceeding 14 months. The dismal prognosis is primarily attributed to the development of chemoresistance to temozolomide, the primary therapeutic agent for GBA treatment. Hence, it becomes imperative to develop novel drugs with antitumor efficacy rooted in distinct mechanisms compared to temozolomide. The vast marine environment contains a wealth of naturally occurring compounds from the sea (known as marine-derived natural products), which hold promise for future research in the quest for new anticancer drugs. Ongoing advancements in anticancer pharmaceuticals have led to an upswing in the isolation and validation of numerous pioneering breakthroughs and improvements in anticancer therapeutics. Nonetheless, the availability of FDA-approved marine-derived anticancer drugs remains limited, owing to various challenges and constraints. Among these challenges, drug delivery is a prominent hurdle. This review delves into an alternative approach for delivering marine-derived drugs using nanotechnological formulations and their mechanism of action for treating GBA.

Targeting phosphodiesterase 4 as a potential therapy for Parkinson's disease: a review

Phosphodiesterases (PDEs) have become a promising therapeutic target for various disorders. PDEs are a vast and diversified family of enzymes that degrade cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), which have several biochemical and physiological functions. Phosphodiesterase 4 (PDE4) is the most abundant PDE in the central nervous system (CNS) and is extensively expressed in the mammalian brain, where it catalyzes the hydrolysis of intracellular cAMP. An alteration in the balance of PDE4 and cAMP results in the dysregulation of different biological mechanisms involved in neurodegenerative diseases. By inhibiting PDE4 with drugs, the levels of cAMP inside the cells could be stabilized, which may improve the symptoms of mental and neurological disorders such as memory loss, depression, and Parkinson's disease (PD). Though numerous studies have shown that phosphodiesterase 4 inhibitors (PDE4Is) are beneficial in PD, there are presently no approved PDE4I drugs for PD. This review presents an overview of PDE4Is and their effects on PD, their possible underlying mechanism in the restoration/protection of dopaminergic cell death, which holds promise for developing PDE4Is as a treatment strategy for PD. Methods on how these drugs could be effectively delivered to develop as a promising treatment for PD have been suggested.

Polysorbate 80 surface modified SLNs of formoterol suppress SNCA gene and mitochondrial oxidative stress in mice model of Parkinson's disease

The present study hypothesises that the selective brain β2 receptor activation through β2-adrenoreceptor agonist (β2ARA), Formoterol (FMT), suppresses SNCA gene expression, a pathological hallmark of Parkinson's disease (PD) in brain. Further, it is also hypothesized that brain targeted delivery of Formoterol via polysorbate-80 surface modified solid lipid nanoparticles of Formoterol (FMT-SLNs-PS80) can improve its stability, therapeutic efficacy and avoid/reduce peripheral off-target side effects. FMT-SLNs-PS80 was prepared by solvent injection method, the formulation was optimized by using Box-Behnken design and characterized by measuring drug content, entrapment efficacy, particle size, zeta potentials and poly dispersibility. The FMT-SLNs-PS80, significantly decreases the SNCA expression, mitochondrial membrane damage and rotenone induced changes in oxidative (SOD, CAT, GSH and ROS) stress markers in SH-SY5Y cell lines. The ex vivo permeation study of the formulation using everted chicken ileum exhibited a steady state flux. The pharmacokinetic and tissue distribution studies of the formulation in rats showed a significant improvement in the kinetic parameters when compared to naïve FMT, further the formulation also improved the brain bioavailability of FMT. The anti-Parkinson's efficacy studies of the formulation in mice showed a significant neuroprotection against rotenone-induced changes in behavioural and biochemical parameters. Further, the histopathological analysis of mice brain confirms a significant neuroprotective benefit. The present study successfully establishes the brain targeted delivery and anti-Parkinson's therapeutic efficacy of FMT-SLNs-PS80.

The identification of cianidanol as a selective estrogen receptor beta agonist and evaluation of its neuroprotective effects on Parkinson's disease models

AIM

The present study aims to identify selective estrogen receptor beta (ERβ) agonists and to evaluate the neuroprotective mechanism in Parkinson's disease (PD) models.

MAIN METHODS

In-silico studies were carried out using Maestro and GROMACS. Neuroprotective activity and apoptosis were evaluated using cytotoxicity assay and flow cytometry respectively. Gene expression studies were carried out by reverse transcription polymerase chain reaction. Motor and cognitive functions were assessed by actophotometer, rotarod, catalepsy, and elevated plus maze. The neuronal population in the substantia nigra and striatum of rats was assessed by hematoxylin and eosin staining.

KEY FINDINGS

Cianidanol was identified as a selective ERβ agonist through virtual screening. The cianidanol-ERβ complex is stable during the 200 ns simulation and was able to retain the interactions with key amino acid residues. Cianidanol (25 μM) prevents neuronal toxicity and apoptosis induced by rotenone in differentiated SH-SY5Y cells. Additionally, cianidanol (25 μM) increases the expression of ERβ, cathepsin D, and Nrf2 transcripts. The neuroprotective effects of cianidanol (25 μM) were reversed in the presence of a selective ERβ antagonist. In this study, we found that selective activation of ERβ could decrease the transcription of α-synuclein gene. Additionally, cianidanol (10, 20, 30 mg/kg, oral) improves the motor and cognitive deficit in rats induced by rotenone.

SIGNIFICANCE

Cianidanol shows neuroprotective action in PD models and has the potential to serve as a novel therapeutic agent for the treatment of PD.

Phosphodiesterase-4 Inhibition in Parkinson's Disease: Molecular Insights and Therapeutic Potential

Clinicians and researchers are exploring safer and novel treatment strategies for treating the ever-prevalent Parkinson's disease (PD) across the globe. Several therapeutic strategies are used clinically for PD, including dopamine replacement therapy, DA agonists, MAO-B blockers, COMT blockers, and anticholinergics. Surgical interventions such as pallidotomy, particularly deep brain stimulation (DBS), are also employed. However, they only provide temporal and symptomatic relief. Cyclic adenosine monophosphate (cAMP) is one of the secondary messengers involved in dopaminergic neurotransmission. Phosphodiesterase (PDE) regulates cAMP and cGMP intracellular levels. PDE enzymes are subdivided into families and subtypes which are expressed throughout the human body. PDE4 isoenzyme- PDE4B subtype is overexpressed in the substantia nigra of the brain. Various studies have implicated multiple cAMP-mediated signaling cascades in PD, and PDE4 is a common link that can emerge as a neuroprotective and/or disease-modifying target. Furthermore, a mechanistic understanding of the PDE4 subtypes has provided perceptivity into the molecular mechanisms underlying the adverse effects of phosphodiesterase-4 inhibitors (PDE4Is). The repositioning and development of efficacious PDE4Is for PD have gained much attention. This review critically assesses the existing literature on PDE4 and its expression. Specifically, this review provides insights into the interrelated neurological cAMP-mediated signaling cascades involving PDE4s and the potential role of PDE4Is in PD. In addition, we discuss existing challenges and possible strategies for overcoming them.

Novel therapeutic interventions for combating Parkinson's disease and prospects of Nose-to-Brain drug delivery

Parkinson disease (PD) is a progressive neurodegenerative disorder prevalent mainly in geriatric population. While, L-DOPA remains one of the major choices for the therapeutic management of PD, various motor and non-motor manifestations complicate the management of PD. In the last two decades, exhaustive research has been carried out to explore novel therapeutic approaches for mitigating motor and non-motor symptoms of PD. These approaches majorly include receptor-based, anti-inflammatory, stem-cell and nucleic acid based. The major limitations of existing therapeutic interventions (of commonly oral route) are low efficacy due to low brain bioavailability and associated side effects. Nanotechnology has been exploited and has gained wide attention in the recent years as an approach for enhancement of bioavailability of various small molecule drugs in the brain. To address the challenges associated with PD therapy, nose-to-brain delivery utilizing nanomedicine-based approaches has been found to be encouraging in published evidence. Therefore, the present work summarises the major challenges and limitations with antiparkinsonian drugs, novel therapeutic interventions, and scope of nanomedicine-based nose-to-brain delivery in addressing the current challenges of antiparkinsonian therapy. The manuscript tries to sensitize the researchers for designing brain-targeted nanomedicine loaded with natural/synthetic scaffolds, biosimilars, and nucleic acids that can bypass the first-pass effect for the effective management of PD.

Association between β2-Adrenoreceptor Medications and Risk of Parkinson's Disease: A Meta-Analysis

Background and Objective: Parkinson’s disease (PD) is a progressive neurological disorder characterized by an accumulation of Lewy bodies and degeneration of dopaminergic neurons in the substantia nigra. The treatment options currently available are only partly effective and fail to restore the lost dopaminergic neurons or slow the progression. β2-adrenoceptors (β2AR) are widely expressed in various human tissues and organs, regulate many important metabolic functions, and are targeted for treatment of various diseases. Studies have reported a link between chronic use of the β2AR antagonist propranolol and an increased risk of PD, and chronic use of β2AR agonists has been associated with a decreased risk of PD. We conducted a meta-analysis on the association between both β2AR agonist level and β2AR antagonist level and the risk of PD. Materials and Methods: A comprehensive electronic search was conducted on the databases of PubMed, ScienceDirect, ProQuest, Cochrane Library, and ClinicalKey from the start of each database until 30 June 2021. The objective was to identify prospective cohort and case–control studies that have reported on the association between β-adrenoceptor agonist level, antagonist level, and PD risk. Results: A meta-analysis of the data extracted from eight studies revealed that β2AR agonist use was associated with reduced PD risk (RR = 0.859, 95% confidence interval [CI] 0.741–0.995. p = 0.043). Compared with the control group, β2AR antagonist use was associated with an increased risk of PD (RR = 1.490, 95% CI, 1.195 to 1.857. p < 0.005). Propranolol, a type of β2AR antagonist, was related to an increased risk of PD (RR = 2.820, 95% CI, 2.618 to 3.036. p < 0.005). Conclusions: In this meta-analysis, β2AR agonists were associated with a decreased risk of PD, and β2AR antagonists were related with an increased risk of PD. However, further studies with larger sample sizes and an evaluation of the long-term effects of varying dosages of medications are needed.

Biomaterials in the treatment of Parkinson's disease

Parkinson's disease is a neurodegenerative disease, the treatment of which is mainly centred around supplementation of dopamine. Additional targets have been identified and newer chemotherapeutic agents have been introduced but their clinical efficacy is limited due to solubility, bioavailability issues and inability to cross the blood-brain barrier (BBB). A wide range of biomaterials ranging from biomolecules, polymers, inorganic metal and metal oxide nanoparticles have been employed to assist the delivery of these therapeutic agents into the brain. Additionally, strategies to deliver cells to restore the dopaminergic neurons also have shown promise due to the integration of biocompatible materials that aid neurogenesis through a combination of topographical, chemical and mechanical cues. Neuroprosthetics is an area that may become significant in treatment of motor deficits associated with Parkinson's disease, and involves development of highly conductive and robust electrode materials with excellent cytocompatibility. This review summarizes the major role played by biomaterials in design of novel strategies and in the improvement of existing therapeutic methods as well as the emerging trends in this domain.