Parkinson's disease

Overview

Parkinson's disease is a progressive neurodegenerative disorder characterized primarily by the loss of dopaminergic neurons in the substantia nigra and by the accumulation of misfolded α-synuclein. Clinically, it causes motor symptoms such as bradykinesia, rigidity, tremor, and postural instability, as well as a broad range of non-motor manifestations including cognitive impairment, anxiety, sleep disturbance, autonomic dysfunction, and gastrointestinal symptoms. Aging is the strongest risk factor, and disease heterogeneity is increasingly recognized across prodromal, early, and advanced stages.

Biologically, Parkinson's disease is associated with mitochondrial dysfunction, oxidative stress, neuroinflammation, autophagy-lysosomal impairment, lipid dysregulation, ferroptosis, and altered gut-brain axis signaling. Recent research also highlights genetic contributors such as LRRK2, PINK1/Parkin, c-Abl, and pathways involving PARP1, NLRP3 inflammasome activation, cGAS-STING signaling, and TLR4-mediated inflammation. These mechanisms have made Parkinson's disease a major focus for biomarker discovery, disease-modifying therapy development, and device-aided symptomatic treatment.

Focus of Latest Publications

The recent publications provided show Parkinson's disease being used as a central disease target across mechanistic, translational, diagnostic, and therapeutic studies. Several papers focused on neuroprotective or disease-modifying strategies in experimental models. Glimepiride was reported to have neuroprotective effects in ischemic stroke and Parkinson's disease models, while sulforaphane was studied as an H2S donor that inhibits NLRP3 inflammasome activation by inducing mitochondrial autophagy and mitigating CBS-H2S axis damage in in-vitro and in-vivo models. Other experimental compounds included HM568, which was linked to enhanced NAD+ biosynthesis and reduced mitochondrial dysfunction and neurotoxicity through putative PARP1 modulation; astragaloside IV, which alleviated motor and anxiety deficits in Parkinson's disease mice by targeting TLR4; and a sigma-1-receptor agonist, 1,3-di-o-tolylguanidine, which showed neuroprotective effects in a rotenone-induced rat model. Additional studies examined betanin derivatives, urolithin A, DPP-4 inhibitors such as sitagliptin and vildagliptin, and a potent icaritin derivative, all in the context of oxidative stress, α-synuclein aggregation, mitophagy restoration, or dopaminergic neuroprotection.

Mitochondrial quality control and proteostasis were recurring themes. Multiple studies emphasized PINK1/Parkin-mediated mitophagy, mitochondrial dysfunction, and disrupted lipid homeostasis as central to Parkinson's disease pathogenesis. One review addressed the OMA1-DELE1-HRI axis together with PINK1-parkin-mediated mitophagy, while another linked mitochondrial dysfunction to neurodegeneration and oxidative stress. Related work examined S100A9 inhibition to mitigate aging-related mitochondrial dysfunction and neurodegeneration, and PRDX2-mediated neuroprotection via the CYP2J2/8,9-EET pathway in Parkinson's disease models. The disease was also connected to PARP1 overactivation, ferroptosis, calcineurin dysregulation, and cGAS-STING activation as potential therapeutic entry points.

A substantial portion of the literature addressed α-synuclein biology, inflammation, and the gut-brain axis. Studies described Parkinson's disease as a disorder marked by abnormal α-synuclein deposition, oxidative stress-driven degeneration of dopaminergic neurons, and microglia-mediated neuroinflammatory responses. One paper on carbon quantum dots reported exacerbation of Parkinson's disease-like pathology through microglial neuroinflammation, underscoring toxicological implications. Another study on engineered exosomes and autophagy-targeting chimeric Peptides focused on degradation of aggregated α-synuclein. Gut microbiota and host metabolism were also prominent: repeated donor fecal transplantation improved motor and gastrointestinal symptoms in drug-naïve Parkinson's disease in a randomized phase 2 trial, and multi-omics studies linked gut microbial composition, metabolic alterations, and epigenetic pathways to disease heterogeneity. Akkermansia muciniphila was discussed as a double-edged component of life-stage-specific nutritional modulation via the gut-brain axis.

Clinical and real-world studies in the provided set focused on diagnosis, prognosis, and treatment optimization. A nationwide claims-based case-control study in Taiwan examined clinical associations during the year before Parkinson's disease diagnosis to better define the diagnostic window. Biomarker-oriented work included cerebrospinal fluid protein-based early diagnosis using a benchmarking-validated transformer framework, serum exosome spectroscopy with machine learning, blood-based ferroptosis biomarkers, and personalized metabolite biomarker predictions revealing heterogeneous disease characteristics. Other studies used handwriting biomarkers, voice-based multiclass classification, and AI-driven prediction models to support detection or severity assessment. Several papers also addressed stakeholder perspectives on digital technologies and the trustworthiness of clinical AI in Parkinson disease care.

Therapeutic management and device-aided care were another major focus. Continuous subcutaneous foslevodopa/foscarbidopa was evaluated in advanced Parkinson's disease in cost-impact, real-world safety, and effectiveness studies, reflecting its role as an emerging nonsurgical infusion therapy for motor fluctuations. levodopa formulations, including levodopa/carbidopa/entacapone and levodopa/benserazide, were compared in a randomized trial measuring blood dopamine. COMT inhibitors were studied through patient-reported outcomes and experiences in motor fluctuation management, and ropinirole was examined in a pharmacokinetic study of intranasal delivery. Deep brain stimulation remained central, with studies on long-term electrode-tissue interface effects, cognitive outcomes, adaptive stimulation, and the impact of subthalamic nucleus stimulation on attention, processing speed, balance, sleep, and motor complications. Transcranial ultrasound stimulation and piezoelectric neuromodulation of the subthalamic nucleus were also explored as newer neuromodulatory approaches.

Several publications addressed genetics, omics, and biomarker discovery. LRRK2 was highlighted as a gene implicated in Parkinson's disease and aging-related phenotypes. OBPIIa variants were associated with prodromal parkinsonian phenotypes and dopaminergic biomarkers. Multi-omics analyses of the substantia nigra pars compacta across Braak stages, blood microbial signatures, and pan-neurodegeneration proteomics all aimed to define molecular subtypes and disease progression signatures. CRISPR-Cas systems were reviewed as potential therapeutic avenues, and graph-based gene discovery approaches were used to identify Parkinson's disease-associated genes for drug repurposing. Across these studies, Parkinson's disease was consistently treated as a biologically complex, clinically heterogeneous disorder with multiple converging pathogenic pathways and a broad therapeutic research landscape.

Key Publications

• NEWJun Effects of levodopa on the motor reserve network change with progression of Parkinson's disease. (Progress in neuro-psychopharmacology & biological psychiatry, 2026, PMID 42190988): "Recent studies have highlighted the role of the motor reserve network (MRN) in early-stage Parkinson's disease (PD)."
• Jun Reflexive eye movement alterations are related to subclinical impulsive-compulsive behaviors in Parkinson's disease. (Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, 2026, PMID 42319526): "Subclinical impulsive-compulsive behaviors (s-ICBs) in Parkinson's disease (PD) are common, clinically relevant, and frequently underdiagnosed."
• Jun Neuroprotective effects of gallic acid in an MPP⁺-induced SH-sy5y cell model of parkinson's disease. (Molecular biology reports, 2026, PMID 42319576): "Parkinson's Disease (PD) represents the second most prevalent neurodegenerative condition which leads to the progressive destruction of dopaminergic neurons in the substantia nigra through oxidative stress mechanisms."
• Jun Alpha-synuclein fibrils induce budding of mitochondrial-derived vesicles. (Proceedings of the National Academy of Sciences of the United States of America, 2026, PMID 42258734): "α-synuclein (α-syn) aggregation is a hallmark of synucleinopathies, a class of neurodegenerative disorders such as Parkinson's disease (PD)."
• Jun The Association Between Alzheimer's Disease-Related Biomarkers And Parkinson's Disease Based On Single-Cell Sequencing Analysis Combined With Mendelian Randomization. (Journal of molecular neuroscience : MN, 2026, PMID 42298115): "Parkinson's disease (PD) and Alzheimer's disease (AD) are both neurodegenerative disorders sharing overlapping pathological mechanisms."
• Jun Resveratrol isomers with opposing activities target endonuclease G to modulate neurodegeneration and mitochondrial elimination. (Proceedings of the National Academy of Sciences of the United States of America, 2026, PMID 42296341): "In a mouse model of Parkinson's disease, cis-RSV treatment inhibited DA neurodegeneration in the substantia nigra and improved motor symptoms of animals."
• Jun Blood-based biomarkers of ferroptosis in Parkinson's disease. (Neurobiology of disease, 2026, PMID 42035924): "As Parkinson's disease progresses, patients require second-line treatments such as subthalamic stimulation, the benefits of which may be diminished by the onset of non-dopaminergic axial motor and cognitive disorders."
• Jun A potent icaritin derivative ameliorates Parkinson's disease via GPER-mediated mitophagy restoration and dopaminergic neuroprotection. (Bioorganic chemistry, 2026, PMID 41855639): "Molecular docking, pharmacological blockade and studies in GPER knockout mouse models of Parkinson's disease (PD) confirmed that the effects of ICTC depend on GPER."
• Jun Dysphagia after COVID-19 Vaccination: A Report of Two Cases. (Internal medicine (Tokyo, Japan), 2025, PMID 41224265): "Case 2: An 80-year-old man with Parkinson's disease developed aspiration pneumonia and dysphagia."
• Jun Systemic characterization of aging-related phenotypes induced by wild-type and G2019S LRRK2 in Caenorhabditis elegans. (Experimental neurology, 2026, PMID 42270006): "Leucine-rich repeat kinase 2 (LRRK2), initially identified as a gene implicated in Parkinson's disease, is increasingly recognized for its influence on aging and associated disorders."