Ferroptosis as a New Mechanism in Parkinson's Disease Therapy Using Traditional Chinese Medicine

Lasting Impact: Exploring the Brain Mechanisms that Link Traumatic Brain Injury to Parkinson's Disease

Development of Parkinson's Disease (PD) is linked with a history of traumatic brain injury (TBI), although the mechanisms driving this remain unclear. Of note, many key parallels have been identified between the pathologies of PD and TBI; in particular, PD is characterised by loss of dopaminergic neurons from the substantia nigra (SN), accompanied by broader changes to dopaminergic signalling, disruption of the Locus Coeruleus (LC) and noradrenergic system, and accumulation of aggregated α-synuclein in Lewy Bodies, which spreads in a stereotypical pattern throughout the brain. Widespread disruptions to the dopaminergic and noradrenergic systems, including progressive neuronal loss from the SN and LC, have been observed acutely following injury, some of which have also been identified chronically in TBI patients and preclinical models. Furthermore, changes to α-synuclein expression are also seen both acutely and chronically following injury throughout the brain, although detailed characterisation of these changes and spread of pathology is limited. In this review, we detail the current literature regarding dopaminergic and noradrenergic disruption and α-synuclein pathology following injury, with particular focus on how these changes may predispose individuals to prolonged pathology and progressive neurodegeneration, particularly the development of PD. While it is increasingly clear that TBI is a key risk factor for the development of PD, significant gaps remain in current understanding of neurodegenerative pathology following TBI, particularly chronic manifestations of injury.

Role and mechanism of molecular hydrogen in the treatment of Parkinson's diseases

Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by a pathology that includes the aggregation of alpha-synuclein (α-syn), oxidative stress, and neuroinflammation. While existing treatments can alleviate motor symptoms, they have limited efficacy in slowing disease progression and improving non-motor symptoms. In recent years, molecular hydrogen has been recognized for its potential neuroprotective effects, attributed to its selective antioxidant and anti-inflammatory properties. While preclinical studies demonstrate promising results, clinical trials conducted thus far have yielded mixed outcomes, with some trials reporting limited or no therapeutic benefit. This review systematically analyzes the mechanisms of action of molecular hydrogen in PD and related neurodegenerative disorders, emphasizing its antioxidant, anti-inflammatory, and anti-apoptotic properties. By evaluating evidence from both preclinical and clinical studies, this paper explores the potential of molecular hydrogen to attenuate oxidative stress, modulate inflammatory responses, and inhibit apoptosis in neuronal cells, while also identifying key gaps in current research. As a novel neuroprotective agent, molecular hydrogen holds potential in PD and other neurodegenerative diseases, but further well-designed clinical trials are needed to validate its efficacy. Future studies should focus on elucidating the mechanisms through which hydrogen exerts its neuroprotective effects, particularly concerning α-syn aggregation and its clearance pathways, as well as Nrf2-mediated immunomodulation. Furthermore, large-scale, multicenter clinical trials are necessary to establish efficacy benchmarks and personalized delivery protocols.

Emerging Ferroptosis Involvement in Amyotrophic Lateral Sclerosis Pathogenesis: Neuroprotective Activity of Polyphenols

Neurodegenerative diseases are a group of diseases that share common features, such as the generation of misfolded protein deposits and increased oxidative stress. Among them, amyotrophic lateral sclerosis (ALS), whose pathogenesis is still not entirely clear, is a complex neurodegenerative disease linked both to gene mutations affecting different proteins, such as superoxide dismutase 1, Tar DNA binding protein 43, Chromosome 9 open frame 72, and Fused in Sarcoma, and to altered iron homeostasis, mitochondrial dysfunction, oxidative stress, and impaired glutamate metabolism. The purpose of this review is to highlight the molecular targets common to ALS and ferroptosis. Indeed, many pathways implicated in the disease are hallmarks of ferroptosis, a recently discovered type of iron-dependent programmed cell death characterized by increased reactive oxygen species (ROS) and lipid peroxidation. Iron accumulation results in mitochondrial dysfunction and increased levels of ROS, lipid peroxidation, and ferroptosis triggers; in addition, the inhibition of the Xc- system results in reduced cystine levels and glutamate accumulation, leading to excitotoxicity and the inhibition of GPx4 synthesis. These results highlight the potential involvement of ferroptosis in ALS, providing new molecular and biochemical targets that could be exploited in the treatment of the disease using polyphenols.

m6A Demethylase FTO-Mediated Upregulation of BAP1 Induces Neuronal Ferroptosis via the p53/SLC7A11 Axis in the MPP+/MPTP-Induced Parkinson's Disease Model

Background: Parkinson's disease (PD) is a neurodegenerative disorder characterized by the involvement of ferroptosis in its pathological mechanism. In this study, the effects and mechanism of BRCA1-associated protein 1 (BAP1) on neuronal ferroptosis in PD were evaluated. Methods: A PD mouse model was constructed by injecting mice with MPTP. Nissl staining, immunohistochemistry, immunofluorescence, and Prussian blue staining evaluated histopathology and iron distribution. The PD cell model was constructed by subjecting SK-N-SH cells to MPP+. The m6A level of BAP1 was assessed by MeRIP. mRNA levels of BAP1, FTO, IGF2BP1, METTL3, YTHDF2, and SLC7A11 were evaluated utilizing RT-qPCR. Protein levels of BAP1, FTO, IGF2BP1, METTL3, YTHDF2, SLC7A11, and p53 were measured by Western blot. Cell viability was assessed using CCK-8 assay, and TUNEL was used for assessing apoptosis. The levels of MDA, GSH, SOD, and Fe2+ were also measured. The interactions among molecules were verified using RIP assay, dual luciferase reporter assay, and ChIP assay. Results: SK-N-SH cells treated with MPP+ showed a decrease in overall m6A levels of BAP1. FTO facilitated m6A demethylation of BAP1, leading to an increased level of expression of BAP1. m6A-binding protein, YTHDF2 recognized and decayed methylated mRNA of BAP1, leading to the reduced BAP1 stability. The FTO/BAP1 axis promoted MPP+-induced ferroptosis by suppressing SLC7A11. BAP1, in collaboration with p53, reduced the level of expression of SLC7A11. Knocking down BAP1 mitigated ferroptosis in an MPTP mouse model. Conclusion: m6A-mediated modification of BAP1 regulates neuronal ferroptosis by cooperating with p53 to decrease the level of SLC7A11. Thus, BAP1 may be a potential therapeutic target for PD treatment.

Gut Microbiota-Based Interventions for Parkinson's Disease: Neuroprotective Mechanisms and Current Perspective

Recent evidence links gut microbiota alterations to neurodegenerative disorders, including Parkinson's disease (PD). Replenishing the abnormal composition of gut microbiota through gut microbiota-based interventions "prebiotics, probiotics, synbiotics, postbiotics, and fecal microbiota transplantation (FMT)" has shown beneficial effects in PD. These interventions increase gut metabolites like short-chain fatty acids (SCFAs) and glucagon-like peptide-1 (GLP-1), which may protect dopaminergic neurons via the gut-brain axis. Neuroprotective effects of these interventions are mediated by several mechanisms, including the enhancement of neurotrophin and activation of the PI3K/AKT/mTOR signaling pathway, GLP-1-mediated gut-brain axis signaling, Nrf2/ARE pathway, and autophagy. Other pathways, such as free fatty acid receptor activation, synaptic plasticity improvement, and blood-brain and gut barrier integrity maintenance, also contribute to neuroprotection. Furthermore, the inhibition of the TLR4/NF-кB pathway, MAPK pathway, GSK-3β signaling pathway, miR-155-5p-mediated neuroinflammation, and ferroptosis could account for their protective effects. Clinical studies involving gut microbiota-based interventions have shown therapeutic benefits in PD patients, particularly in improving gastrointestinal dysfunction and some neurological symptoms. However, the effectiveness in alleviating motor symptoms remains mild. Large-scale clinical trials are still needed to confirm these findings. This review emphasizes the neuroprotective mechanisms of gut microbiota-based interventions in PD as supported by both preclinical and clinical studies.

Targeting Ferroptosis in Parkinson's Disease: Mechanisms and Emerging Therapeutic Strategies

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra and the accumulation of α-synuclein in the brain. Ferroptosis, a recently identified form of regulated cell death, is critical in PD pathogenesis due to its association with iron deposition, overproduction of reactive oxygen species, iron-dependent lipid peroxidation and impaired lipid peroxidation clearance. This cell death mechanism is closely linked to several pathogenic processes in PD, including α-synuclein aggregation, oxidative stress, mitochondrial dysfunction, microglia-induced neuroinflammation, and neuromelanin accumulation. Given the significant role of ferroptosis in these mechanisms, there is increasing interest in targeting ferroptosis for PD treatment. Several drugs have shown potential in alleviating PD symptoms by inhibiting ferroptosis. This review aims to consolidate current knowledge on ferroptosis in PD and assess the therapeutic potential of anti-ferroptosis drugs, highlighting promising directions for future research and clinical applications.

Putative Adverse Outcome Pathway for Parkinson's Disease-like Symptoms Induced by Silicon Quantum Dots based on In Vivo/Vitro Approaches

Given the commercial proliferation of silicon quantum dots (SiQDs) and their inevitable environmental dispersal, this study critically examines their biological and public health implications, specifically regarding Parkinson's disease. The study investigated the toxicological impact of SiQDs on the onset and development of PD-like symptoms through the induction of ferroptosis, utilizing both in vivo [Caenorhabditis elegans (C. elegans)] and in vitro (SH-SY5Y neuroblastoma cell line) models. Our findings demonstrated that SiQDs, characterized by their stable and water-soluble physicochemical properties, tended to accumulate in neuronal tissues. This accumulation precipitated dopaminergic neurodegeneration, manifested as diminished dopamine-dependent behaviors, and escalated the expression of PD-specific genes in C. elegans. Importantly, the results revealed that SiQDs induced ferritinophagy, a selective autophagy pathway that triggered ferroptosis and resulted in PD-like symptoms, even exacerbating disease progression in biological models. These insights were incorporated into a putatively qualitative and quantitative adverse outcome pathway framework, highlighting the serious neurodegenerative risks posed by SiQDs through ferroptosis pathways. This study provides a multidisciplinary analysis critical for informing policy on the regulation of SiQDs exposure to safeguard susceptible populations and guiding the responsible development of nanotechnologies impacting environmental and public health.

The mechanisms of white matter injury and immune system crosstalk in promoting the progression of Parkinson's disease: a narrative review

Parkinson's disease (PD) is neurodegenerative disease in middle-aged and elderly people with some pathological mechanisms including immune disorder, neuroinflammation, white matter injury and abnormal aggregation of alpha-synuclein, etc. New research suggests that white matter injury may be important in the development of PD, but how inflammation, the immune system, and white matter damage interact to harm dopamine neurons is not yet understood. Therefore, it is particularly important to delve into the crosstalk between immune cells in the central and peripheral nervous system based on the study of white matter damage in PD. This crosstalk could not only exacerbate the pathological process of PD but may also reveal new therapeutic targets. By understanding how immune cells penetrate through the blood-brain barrier and activate inflammatory responses within the central nervous system, we can better grasp the impact of structural destruction of white matter in PD and explore how this process can be modulated to mitigate or combat disease progression. Microglia, astrocytes, oligodendrocytes and peripheral immune cells (especially T cells) play a central role in its pathological process where these immune cells produce and respond to pro-inflammatory cytokines such as tumor necrosis factor (TNF-α), interleukin-1β(IL-1β) and interleukin-6(IL-6), and white matter injury causes microglia to become pro-inflammatory and release inflammatory mediators, which attract more immune cells to the damaged area, increasing the inflammatory response. Moreover, white matter damage also causes dysfunction of blood-brain barrier, allows peripheral immune cells and inflammatory factors to invade the brain further, and enhances microglia activation forming a vicious circle that intensifies neuroinflammation. And these factors collectively promote the neuroinflammatory environment and neurodegeneration changes of PD. Overall, these findings not only deepen our understanding of the complexity of PD, but also provide new targets for the development of therapeutic strategies focused on inflammation and immune regulation mechanisms. In summary, this review provided the theoretical basis for clarifying the pathogenesis of PD, summarized the association between white matter damage and the immune cells in the central and peripheral nervous systems, and then emphasized their potential specific mechanisms of achieving crosstalk with further aggravating the pathological process of PD.

Mechanisms of ferroptosis in nonalcoholic fatty liver disease and therapeutic effects of traditional Chinese medicine: a review

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive accumulation of fat in hepatocytes (nonalcoholic fatty liver (NAFL)), and lobular inflammation and hepatocyte damage (which characterize nonalcoholic steatohepatitis (NASH) are found in most patients). A subset of patients will gradually develop liver fibrosis, cirrhosis, and eventually hepatocellular carcinoma, which is a deadly disease that threatens human life worldwide. Ferroptosis, a novel nonapoptotic form of programmed cell death (PCD) characterized by iron-dependent accumulation of reactive oxygen radicals and lipid peroxides, is closely related to NAFLD. Traditional Chinese medicine (TCM) has unique advantages in the prevention and treatment of NAFLD due to its multicomponent, multipathway and multitarget characteristics. In this review, we discuss the effect of TCM on NAFLD by regulating ferroptosis, in order to provide reference for the further development and application of therapeutic drugs to treat NAFLD.

Role of ferroptosis pathways in neuroinflammation and neurological disorders: From pathogenesis to treatment

Ferroptosis is a newly discovered non-apoptotic and iron-dependent type of cell death. Ferroptosis mainly takes place owing to the imbalance of anti-oxidation and oxidation in the body. It is regulated via a number of factors and pathways both inside and outside the cell. Ferroptosis is closely linked with brain and various neurological disorders (NDs). In the human body, the brain contains the highest levels of polyunsaturated fatty acids, which are known as lipid peroxide precursors. In addition, there is also a connection of glutathione depletion and lipid peroxidation with NDs. There is growing evidence regarding the possible link between neuroinflammation and multiple NDs, such as Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, Huntington's disease, and stroke. Recent studies have demonstrated that disruptions of lipid reactive oxygen species (ROS), glutamate excitatory toxicity, iron homeostasis, and various other manifestations linked with ferroptosis can be identified in various neuroinflammation-mediated NDs. It has also been reported that damage-associated molecular pattern molecules including ROS are generated during the events of ferroptosis and can cause glial activation via activating neuroimmune pathways, which subsequently leads to the generation of various inflammatory factors that play a role in various NDs. This review summarizes the regulation pathways of ferroptosis, the link between ferroptosis as well as inflammation in NDs, and the potential of a range of therapeutic agents that can be used to target ferroptosis and inflammation in the treatment of neurological disorders.

Targeting ferroptosis unveils a new era for traditional Chinese medicine: a scientific metrology study

In the past 11 years, there has been a surge in studies exploring the regulatory effect of Traditional Chinese Medicine (TCM) on ferroptosis. However, a significant gap persists in comprehensive scientometric analysis and scientific mapping research, especially in tracking the evolution, primary contributors, and emerging research focal points. This study aims to comprehensively update the advancements in targeting ferroptosis with various TCMs during the previous 11 years. The data, covering the period from 1 January 2012, to 30 November 2023, were retrieved from the Web of Science database. For in-depth scientometric and visualized analyses, a series of advanced analytical instruments were employed. The findings highlight China's predominant role, accounting for 71.99% of total publications and significantly shaping research in this domain. Noteworthy productivity was observed at various institutions, including Guangzhou University of Chinese Medicine, Chengdu University of Traditional Chinese Medicine, and Zhejiang University. Thomas Efferth emerged as the foremost author within this field, while Frontiers in Pharmacology boasted the highest publication count. This study pinpointed hepatocellular carcinoma, chemical and drug-induced liver injury, mitochondrial diseases, acute kidney injury, and liver failure as the most critical disorders addressed in this research realm. The research offers a comprehensive bibliometric evaluation, enhancing our understanding of the present status of TCM therapy in managing ferroptosis-related diseases. Consequently, it aids both seasoned researchers and newcomers by accelerating access to vital information and fostering innovative concept extraction within this specialized field.

Ferroptosis: Emerging Role in Diseases and Potential Implication of Bioactive Compounds

Ferroptosis is a form of cell death that is distinguished from other types of death for its peculiar characteristics of death regulated by iron accumulation, increase in ROS, and lipid peroxidation. In the past few years, experimental evidence has correlated ferroptosis with various pathological processes including neurodegenerative and cardiovascular diseases. Ferroptosis also is involved in several types of cancer because it has been shown to induce tumor cell death. In particular, the pharmacological induction of ferroptosis, contributing to the inhibition of the proliferative process, provides new ideas for the pharmacological treatment of cancer. Emerging evidence suggests that certain mechanisms including the Xc- system, GPx4, and iron chelators play a key role in the regulation of ferroptosis and can be used to block the progression of many diseases. This review summarizes current knowledge on the mechanism of ferroptosis and the latest advances in its multiple regulatory pathways, underlining ferroptosis' involvement in the diseases. Finally, we focused on several types of ferroptosis inducers and inhibitors, evaluating their impact on the cell death principal targets to provide new perspectives in the treatment of the diseases and a potential pharmacological development of new clinical therapies.

Deeper insight into ferroptosis: association with Alzheimer's, Parkinson's disease, and brain tumors and their possible treatment by nanomaterials induced ferroptosis

Ferroptosis is an emerging and novel type of iron-dependent programmed cell death which is mainly caused by the excessive deposition of free intracellular iron in the brain cells. This deposited free iron exerts a ferroptosis pathway, resulting in lipid peroxidation (LiPr). There are mainly three ferroptosis pathways viz. iron metabolism-mediated cysteine/glutamate, and LiPr-mediated. Iron is required by the brain as a redox metal for several physiological activities. Due to the iron homeostasis balance disruption, the brain gets adversely affected which further causes neurodegenerative diseases (NDDs) like Parkinson's and Alzheimer's disease, strokes, and brain tumors like glioblastoma (GBS), and glioma. Nanotechnology has played an important role in the prevention and treatment of these NDDs. A synergistic effect of nanomaterials and ferroptosis could prove to be an effective and efficient approach in the field of nanomedicine. In the current review, the authors have highlighted all the latest research in the field of ferroptosis, specifically emphasizing on the role of major molecular key players and various mechanisms involved in the ferroptosis pathway. Moreover, here the authors have also addressed the correlation of ferroptosis with the pathophysiology of NDDs and theragnostic effect of ferroptosis and nanomaterials for the prevention and treatment of NDDs.

Research progress of ferroptosis in Parkinson's disease: a bibliometric and visual analysis

Background

In recent years, the role of ferroptosis in Parkinson's disease (PD) has become a research hotspot based on evidence of abnormal iron deposition and lipid peroxidation damage in the brains of PD patients. This study aims to examine the relevant research on ferroptosis and PD from a bibliometric perspective.

Methods

Original research and review articles related to ferroptosis and PD were retrieved from the Web of Science Core Collection (WOSCC) database. Statistical analysis and visualization of information including countries, institutions, authors, journals, and keywords of the included studies were conducted using the R software package "bibliometrix."

Results

A total of 414 articles met the inclusion criteria, averaging 37.86 citations per article. From 2012 to 2022, the average annual growth rate of research in this area was 63.44%. The corresponding authors of published articles were mainly affiliated with institutions in China, the United States, and Australia. Shanghai Jiao Tong University in China and the University of Melbourne in Australia emerged as the most active and influential institutions. The journal with the highest H-index and publication output was Free Radical Biology and Medicine. "Ferroptosis," "immunotherapy," "prognosis" and "microenvironment" were identified as high-frequency keywords, indicating current and future research directions in this field.

Conclusion

This bibliometric study provides insights into current research hotspots and emerging trends in the growing field of ferroptosis research related to PD. The high-frequency keywords identified highlight active areas of investigation involving methods, mechanisms, and populations of interest.

Chrysophanol improves memory impairment and cell injury by reducing the level of ferroptosis in Aβ25-35 treated rat and PC12 cells

Alzheimer's disease (AD) is a common age-related chronic and neurodegenerative disease that has become a global health problem. AD pathogenesis is complex, and the clinical efficacy of commonly used anti-AD drugs is suboptimal. Recent research has revealed a close association between AD-induced damage and the activation of ferroptosis signaling pathways. Chrysophanol (CHR) the principal medicinal component of Rhubarb, has been reported to have anti-AD effects and can reduce ROS levels in AD-damaged models. AD has been linked to the activation of ferroptosis signaling pathways, which has an important feature of higher levels of reactive oxygen species (ROS). Therefore, the present study explored whether CHR had an anti-AD effect by regulating the ferroptosis levels in AD injury models. Morris water maze, novel object recognition test, Y-maze test, Hematoxylin-eosin (H&E) staining, western blotting, ROS measurement, GPx activity measurement, LPO measurement, transmission electron microscopy, live/dead cell staining were used to investigate the changes in spatial memory level and ferroptosis level in AD model, and the intervention effect of CHR. CHR improved the spatial memory level of AD rat models, reduced the level of hippocampal neuron damage, and improved the survival rate of PC12 cells damaged by β-amyloid (Aβ). Meanwhile, CHR increased glutathione peroxidase-4 (GPX4) protein expression, GPx activity, and GSH, decreased ROS and LPO levels in AD rat models and Aβ-damaged PC12 cells, and improved mitochondrial pathological damage. Our findings suggest that CHR may play a protective role in AD injury by lowering ferroptosis levels, which may provide a potential pathway for developing drugs for AD. However, the mechanism of CHR's role requires further investigation.

Rapamycin reverses ferroptosis by increasing autophagy in MPTP/MPP+-induced models of Parkinson's disease

Parkinson's disease is a neurodegenerative disorder, and ferroptosis plays a significant role in the pathological mechanism underlying Parkinson's disease. Rapamycin, an autophagy inducer, has been shown to have neuroprotective effects in Parkinson's disease. However, the link between rapamycin and ferroptosis in Parkinson's disease is not entirely clear. In this study, rapamycin was administered to a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson's disease mouse model and a 1-methyl-4-phenylpyridinium-induced Parkinson's disease PC12 cell model. The results showed that rapamycin improved the behavioral symptoms of Parkinson's disease model mice, reduced the loss of dopamine neurons in the substantia nigra pars compacta, and reduced the expression of ferroptosis-related indicators (glutathione peroxidase 4, recombinant solute carrier family 7, member 11, glutathione, malondialdehyde, and reactive oxygen species). In the Parkinson's disease cell model, rapamycin improved cell viability and reduced ferroptosis. The neuroprotective effect of rapamycin was attenuated by a ferroptosis inducer (methyl (1S,3R)-2-(2-chloroacetyl)-1-(4-methoxycarbonylphenyl)-1,3,4,9-tetrahyyridoindole-3-carboxylate) and an autophagy inhibitor (3-methyladenine). Inhibiting ferroptosis by activating autophagy may be an important mechanism by which rapamycin exerts its neuroprotective effects. Therefore, the regulation of ferroptosis and autophagy may provide a therapeutic target for drug treatments in Parkinson's disease.

Ferroptosis and Traditional Chinese Medicine for Type 2 Diabetes Mellitus

Ferroptosis, an emerging form of regulated programmed cell death, has garnered significant attention in the past decade. It is characterized by the accumulation of lipid peroxides and subsequent damage to cellular membranes, which is dependent on iron. Ferroptosis has been implicated in the pathogenesis of various diseases, including tumors and diabetes mellitus. Traditional Chinese medicine (TCM) has unique advantages in preventing and treating type 2 diabetes mellitus (T2DM) due to its anti-inflammatory, antioxidant, immunomodulatory, and intestinal flora-regulating functions. Recent studies have determined that TCM may exert therapeutic effects on T2DM and its complications by modulating the ferroptosis-related pathways. Therefore, a comprehensive and systematic understanding of the role of ferroptosis in the pathogenesis and TCM treatment of T2DM is of great significance for developing therapeutic drugs for T2DM and enriching the spectrum of effective T2DM treatment with TCM. In this review, we review the concept, mechanism, and regulatory pathways of ferroptosis and the ferroptosis mechanism of action involved in the development of T2DM. Also, we develop a search strategy, establish strict inclusion and exclusion criteria, and summarize and analyze the application of the ferroptosis mechanism in TCM studies related to T2DM and its complications. Finally, we discuss the shortcomings of current studies and propose a future research focus.

Moxibustion treatment for Parkinson's disease: study protocol for a randomized controlled trial

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder and seriously affects quality of life globally. Moxibustion is widely used to treat neurodegenerative diseases in the clinic and has achieved a beneficial clinical effect. However, strict control and high-quality randomized controlled trials are still lacking. Therefore, this trial aims to evaluate the clinical efficacy and safety of moxibustion in patients with PD and preliminarily explore the underlying mechanism.

METHODS

This is a randomized, single-blind and placebo-controlled trial design in which 70 eligible participants will be randomly divided into a moxibustion group and a sham moxibustion group. Baihui (DU20) and Sishenchong (EX-HN1) are selected for both groups. The treatment will be performed for 30 min per session, two sessions a week for 8 weeks. The mean change in MDS-UPDRS scores (including MDS-UPDRS II, III subscale scores and total scores) from baseline to the observation points will be the primary outcome. The secondary outcomes will include scores on the Parkinson's Disease Questionnaire-39 (PDQ-39), Fatigue Severity Scale (FSS), Parkinson Disease Sleep Scale (PDSS), Montreal Cognitive Assessment (MoCA), and Self-Rating Depression Scale (SDS) as well as the Wexner constipation score. All the above outcomes will be assessed at 4 and 8 weeks. Laboratory blood biochemical analysis and functional magnetic resonance imaging (fMRI) will be conducted at baseline and at the end of treatment to explore the potential mechanisms of moxibustion in regulating PD.

DISCUSSION

In conclusion, the results of this trial will reveal whether moxibustion is effective for treating motor and nonmotor symptoms in PD. This trial will also preliminarily explore the underlying mechanism of the regulatory effect of moxibustion in PD, which will contribute to providing a theoretical basis for the treatment of PD.

TRIAL REGISTRATION

ClinicalTrials.gov ChiCTR2000029745. Registered on 9 August 2021.

Research Models to Study Ferroptosis's Impact in Neurodegenerative Diseases

Ferroptosis is a type of regulated cell death promoted by the appearance of oxidative perturbations in the intracellular microenvironment constitutively controlled by glutathione peroxidase 4 (GPX4). It is characterized by increased production of reactive oxygen species, intracellular iron accumulation, lipid peroxidation, inhibition of system Xc-, glutathione depletion, and decreased GPX4 activity. Several pieces of evidence support the involvement of ferroptosis in distinct neurodegenerative diseases. In vitro and in vivo models allow a reliable transition to clinical studies. Several in vitro models, including differentiated SH-SY5Y and PC12 cells, among others, have been used to investigate the pathophysiological mechanisms of distinct neurodegenerative diseases, including ferroptosis. In addition, they can be useful in the development of potential ferroptosis inhibitors that can be used as disease-modifying drugs for the treatment of such diseases. On the other hand, in vivo models based on the manipulation of rodents and invertebrate animals, such as Drosophila melanogaster, Caenorhabditis elegans, and zebrafish, have been increasingly used for research in neurodegeneration. This work provides an up-to-date review of the main in vitro and in vivo models that can be used to evaluate ferroptosis in the most prevalent neurodegenerative diseases, and to explore potential new drug targets and novel drug candidates for effective disease-modifying therapies.

Mechanisms of the Ping-wei-san plus herbal decoction against Parkinson's disease: Multiomics analyses

Introduction

Parkinson's disease is a neurodegenerative disorder involving loss of dopaminergic neurons. Multiple studies implicate the microbiota-gut-brain axis in Parkinson's disease pathophysiology. Ping-wei-san plus Herbal Decoction, a traditional Chinese medicine composition with beneficial effects in Parkinson's disease, may have a complex array of actions. Here we sought to determine whether gut microbiota and metabolic pathways are involved in Ping-wei-san plus herbal therapy for Parkinson's disease and to identify functional pathways to guide research.

Methods and results

The model of Parkinson's disease were induced with the rotenone. The Ping-wei-san plus group received the PWP herbal decoction for 90 days, after which all groups were analyzed experimentally. PWP herbal treatment improved motor behavior and emotional performance, balanced gut microbiota, and benefited dietary metabolism. Tandem Mass Tags mass spectrometry identified many differentially expressed proteins (DEPs) in the substantia nigra and duodenum in the PWP group, and these DEPs were enriched in pathways such as those involving cAMP signaling, glutamatergic synapses, dopaminergic synapses, and ribosome-rich functions in the gut. The PWP group showed increases in recombinant tissue inhibitors of metalloproteinase 3, and nucleotide-binding oligomerization domain, leucine rich repeat, and pyrin domain containing proteins 6 in the substantia nigra and decreased parkin, gasdermin D, recombinant tissue inhibitors of metalloproteinase 3, and nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing proteins 6 in the duodenum.

Discussion

In conclusion, this study combined gut microbiota, metabolomics, and proteomics to evaluate the mechanism of action of Ping-wei-san plus on Parkinson's disease and revealed that PWP herbal treatment modulated gut microbiota, altered metabolite biological pathways, and affected functional pathway protein expression in Parkinson's disease mice, resulting in therapeutic effects.

Pharmacological Activity, Pharmacokinetics, and Clinical Research Progress of Puerarin

As a kind of medicine and food homologous plant, kudzu root (Pueraria lobata (Willd.) Ohwi) is called an "official medicine" in Chinese folk medicine. Puerarin is the main active component extracted from kudzu root, and its structural formula is 8-β-D-grapes pyranose-4, 7-dihydroxy isoflavone, with a white needle crystal; it is slightly soluble in water, and its aqueous solution is colorless or light yellow. Puerarin is a natural antioxidant with high health value and has a series of biological activities such as antioxidation, anti-inflammation, anti-tumor effects, immunity improvement, and cardio-cerebrovascular and nerve cell protection. In particular, for the past few years, it has also been extensively used in clinical study. This review focuses on the antioxidant activity of puerarin, the therapy of diverse types of inflammatory diseases, various new drug delivery systems of puerarin, the "structure-activity relationship" of puerarin and its derivatives, and pharmacokinetic and clinical studies, which can provide a new perspective for the puerarin-related drug research and development, clinical application, and further development and utilization.

Ferroptosis of Endothelial Cells in Vascular Diseases

Endothelial cells (ECs) line the inner surface of blood vessels and play a substantial role in vascular biology. Endothelial dysfunction (ED) is strongly correlated with the initiation and progression of many vascular diseases. Regulated cell death, such as ferroptosis, is one of the multiple mechanisms that lead to ED. Ferroptosis is an iron-dependent programmed cell death associated with various vascular diseases, such as cardiovascular, cerebrovascular, and pulmonary vascular diseases. This review summarized ferroptosis of ECs in vascular diseases and discussed potential therapeutic strategies for treating ferroptosis of ECs. In addition to lipid peroxidation inhibitors and iron chelators, a growing body of evidence showed that clinical drugs, natural products, and intervention of noncoding RNAs may also inhibit ferroptosis of ECs.

Protective effect of traditional Chinese medicine on non-alcoholic fatty liver disease and liver cancer by targeting ferroptosis

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease with high incidence and is closely related to metabolic syndrome. If not controlled, it may eventually become hepatocellular carcinoma (HCC). Ferroptosis, a non-apoptotic form of programmed cell death (PCD), is closely related to NAFLD and HCC, and the mechanisms of action involved are more complex. Some studies have demonstrated that many drugs inhibit ferroptosis and protect liver steatosis or carcinogenesis. The role of Traditional Chinese Medicine (TCM), especially herbs or herbal extracts, has received increasing attention. However, there are relatively few review articles on the regulation of NAFLD by TCM through ferroptosis pathway. Here, we summarize the TCM intervention mechanism and application affecting NAFLD/NAFLD-HCC via regulation of ferroptosis. This article focuses on the relationship between ferroptosis and NAFLD or NAFLD-HCC and the protective effect of TCM on both by targeting ferroptosis. It not only summarizes the mechanism of early prevention and treatment of NAFLD, but also provides reference ideas for the development of TCM for the treatment of metabolic diseases and liver diseases.

Oxidative Stress and Mitochondrial Complex I Dysfunction Correlate with Neurodegeneration in an α-Synucleinopathy Animal Model

The α-synucleinopathies constitute a subset of neurodegenerative disorders, of which Parkinson’s disease (PD) is the most common worldwide, characterized by the accumulation of misfolded α-synuclein in the cytoplasm of neurons, which spreads in a prion-like manner to anatomically interconnected brain areas. However, it is not clear how α-synucleinopathy triggers neurodegeneration. We recently developed a rat model through a single intranigral administration of the neurotoxic β-sitosterol β-D-glucoside (BSSG), which produces α-synucleinopathy. In this model, we aimed to evaluate the temporal pattern of levels in oxidative and nitrosative stress and mitochondrial complex I (CI) dysfunction and how these biochemical parameters are associated with neurodegeneration in different brain areas with α-synucleinopathy (Substantia nigra pars compacta, the striatum, in the hippocampus and the olfactory bulb, where α-syn aggregation spreads). Interestingly, an increase in oxidative stress and mitochondrial CI dysfunction accompanied neurodegeneration in those brain regions. Furthermore, in silico analysis suggests a high-affinity binding site for BSSG with peroxisome proliferator-activated receptors (PPAR) alpha (PPAR-α) and gamma (PPAR-γ). These findings will contribute to elucidating the pathophysiological mechanisms associated with α-synucleinopathies and lead to the identification of new early biomarkers and therapeutic targets.

Epigallocatechin-3-gallate: A phytochemical as a promising drug candidate for the treatment of Parkinson’s disease

Epigallocatechin 3-gallate (EGCG), an abundant polyphenolic component derived from green tea extract, possesses versatile bioactivities that can combat many diseases. During the last decade, EGCG was shown to be effective in experimental models of Parkinson’s disease (PD). Several experimental studies have suggested that it has pleiotropic neuroprotective effects, which has enhanced the appeal of EGCG as a therapeutic strategy in PD. In this review, we compiled recent updates and knowledge of the molecular mechanisms underlying the neuroprotective effects of EGCG in PD. We focused on the effects of EGCG on apoptosis, oxidative stress, inflammation, ferroptosis, modulation of dopamine production, and the aggregation of α-synuclein. The review highlights the pharmacological features of EGCG and its therapeutic implications in PD. Taken together, the accumulated data indicate that EGCG is a promising neuroprotective compound for the treatment of PD.

Modified Iron Deposition in Nigrosomes by Pharmacotherapy for the Management of Parkinson’s Disease

Background: Increased iron deposition in nigrosome as assessed by susceptibility-weighted imaging (SWI) is involved in the pathogenesis of Parkinson’s disease (PD). This study investigated the effects of antiparkinson drugs on iron deposition in the nigrosome of PD patients.

Methods: Based on the retrospective analysis of clinical data, alterations in iron deposition in the substantia nigra were investigated in 51 PD patients across different types of therapies and in nine Parkinson-plus syndrome patients. The Movement Disorder Society revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) Part Ⅲ/Ⅳ (UPDRS Ⅲ/Ⅳ) was utilized to evaluate motor function and complications. SWI (slice = 0.6 mm) was used to detect iron deposition in the nigrosome and substantia nigra. Nigrosome loss was scored on a 1-point nigrosome visibility scale. Visual assessment of dorsolateral nigral hyperintensity (DNH) was separately performed for each side of the nigrosome with SWI.

Results: Increased UPDRS Ⅲ scores were correlated with low nigrosome scores based on correlation analysis at a disease duration of 6–12 months (r = −0.8420). The loss of the nigrosome on SWI was clearly inhibited in PD patients with a 3–5-year duration of administration of antiparkinson medications compared with no treatment. Decreased UPDRS Ⅲ scores and increased nigrosome scores were observed in the regular treatment of PD patients with a 6–7-year disease duration. For patients with Parkinson-plus syndromes, such as multiple system atrophy, iron accumulation was apparent in the corpus striatum and substantia nigra compared with that for patients with progressive supranuclear palsy.

Conclusions: Early and regular treatment with antiparkinson drugs not only alleviates the chance of PD disability but also prevents the loss of DNH, namely, iron accumulation in the nigrosome.

Antioxidative role of Traditional Chinese Medicine in Parkinson's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Neuroprotective Traditional Chinese Medicine (TCM) has been practiced in alternative medicine from early days. TCM-derived neuroprotective compounds, such as Chrysin, Cannabidiol, Toonasinoids, and β-asaron, exert significant effectiveness's towards Parkinson's disease (PD). Further, these neuroprotective TCM showed antioxidative, anti-inflammatory, anti-tumor, anti-septic, analgesic properties. Recent research showed that the reduction in the reactive oxygen species (ROS) decreased the α-synuclein (α-syn) toxicity and enhanced the dopaminergic neuron regenerations, the main hallmarks of PD. Therefore, the neuroprotective effects of novel TCM due to its antiradical activities needed deep investigations.

AIMS OF THE STUDY

This review aims to enlighten the neuroprotective TCM and its components with their antioxidative properties to the scientific community for future research.

METHOD

The relevant information on the neuroprotective TCM was gathered from scientific databases (PubMed, Web of Science, Google Scholar, ScienceDirect, SciFinder, Wiley Online Library, ACS Publications, and CNKI). Information was also gained from MS and Ph.D. thesis, books, and online databases. The literature cited in this review dates from 2001 to June 2, 0201.

RESULTS

Novel therapies for PD are accessible, mostly rely on Rivastigmine and Donepezil, offers to slow down the progression of disease at an early stage but embraces lots of disadvantages. Researchers are trying to find a potential drug against PD, which is proficient at preventing or curing the disease progress, but still needed to be further identified. Oxidative insult and mitochondrial dysfunction are thought to be the main culprit of neurodegenerations. Reactive oxygen species (ROS) are the only causative agent in all interactions, leading to PD, from mitochondrial dysfunctions, α-syn aggregative toxicity, and DA neurons degenerations. It is evident from the redox balance, which seems an imperative therapeutic approach against PD and was necessary for the significant neuronal activities.

CONCLUSION

Our study is explaining the newly discovered TCM and their neuroprotective and antioxidative properties. But also bring up the possible treatment approaches against PD for future researchers.