Deciphering variability in the role of interleukin-1β in Parkinson's disease

Total Glucosides of White Paeony Capsule ameliorates Parkinson's disease-like behavior in MPTP-induced mice model by regulating LRRK2/alpha-synuclein signaling

ETHNOPHARMACOLOGICAL RELEVANCE

The Total Glucosides of White Paeony Capsule (TGPC), one of the traditional Chinese patent medicines, has been used for the treatment of autoimmune diseases such as rheumatoid arthritis (RA) in clinical practice. Besides, the components of TGPC are extracted from Radix Paeoniae Alba (RPA) and have displayed neuroprotective properties.

AIM OF THE STUDY

The present study was designed to evaluate the anti-PD-like effects of TGPC on a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mice model and explore its potential molecular mechanisms.

MATERIALS AND METHODS

Behavioral tests, hematoxylin and eosin (HE) staining, Nissl staining, immunohistochemistry (IHC), western blotting (WB) and Enzyme-Linked Immunosorbent Assay (ELISA) were performed in this study.

RESULTS

It was observed that TGPC treatment (150, 300 mg/kg) significantly reversed MPTPinduced PD-like behaviors, such as reduced locomotive activity in the open field test, prolonged time to turn downward on the ball (T-turn) and to climb down the whole pole (T-descend) in the pole test, decreased movement scores in the traction test and extended the latency to fall in the hanging wire test. In addition, TGPC improved neurodegeneration, inhibited the excessive activation of microglia and suppressed the overproduction of proinflammatory cytokines induced by MPTP, partially by restoring leucine-rich repeat kinase 2 (LRRK2) activity and inhibiting alpha-synuclein (α-syn) mediated neuroinflammation signaling.

CONCLUSION

Taken together, TGPC exhibited neuroprotective effects on MPTP-induced mice model of PD, which was associated with the prevention of neuroinflammation and neurodegeneration modulated by LRRK2/α-syn pathway.

Role of NLRP3 inflammasome-mediated neuronal pyroptosis and neuroinflammation in neurodegenerative diseases

BACKGROUND

Neurodegenerative diseases are a common group of neurological disorders characterized by progressive loss of neuronal structure and function leading to cognitive impairment. Recent studies have shown that neuronal pyroptosis mediated by the NLRP3 inflammasome plays a crucial role in the pathogenesis of neurodegenerative diseases.

OBJECTIVE AND METHOD

The NLRP3 inflammasome is a multiprotein complex that, when activated within cells, triggers an inflammatory response, ultimately leading to pyroptotic cell death of neurons. Pyroptosis is a typical pro-inflammatory programmed cell death process occurring downstream of NLRP3 inflammasome activation, characterized by the formation of pores on the cell membrane by the GSDMD protein, leading to cell lysis and the release of inflammatory factors. It has been found that NLRP3 inflammasome-mediated neuronal pyroptosis is closely associated with the development of various neurodegenerative diseases, such as Alzheimer's disease, traumatic brain injury, and Parkinson's disease. Therefore, inhibiting NLRP3 inflammasome activation and attenuating neuronal pyroptosis could potentially serve as novel strategies for the treatment of neurodegenerative diseases.

RESULTS

The aim of this review is to explore the role of NLRP3 activation-mediated neuronal pyroptosis and neuroinflammation in neurodegenerative diseases. Firstly, we extensively discuss the relationship between NLRP3 inflammasome-mediated neuronal pyroptosis and neuroinflammation in various neurodegenerative diseases. Subsequently, we further explore the mechanisms driving NLRP3 activation and assembly, as well as the post-translational modifications regulating NLRP3 inflammasome activation.

CONCLUSION

Understanding these mechanisms will contribute to a deeper understanding of the link between neuronal pyroptosis and neurodegenerative diseases, and hold significant implications for the treatment and prevention of neurodegenerative diseases.

Cause or consequence? The role of IL-1 family cytokines and receptors in neuroinflammatory and neurodegenerative diseases

Cytokines and receptors of the IL-1 family are key mediators in innate immune and inflammatory reactions in physiological defensive conditions, but are also significantly involved in immune-mediated inflammatory diseases. Here, we will address the role of cytokines of the IL-1 superfamily and their receptors in neuroinflammatory and neurodegenerative diseases, in particular Multiple Sclerosis and Alzheimer's disease. Notably, several members of the IL-1 family are present in the brain as tissue-specific splice variants. Attention will be devoted to understanding whether these molecules are involved in the disease onset or are effectors of the downstream degenerative events. We will focus on the balance between the inflammatory cytokines IL-1β and IL-18 and inhibitory cytokines and receptors, in view of future therapeutic approaches.

Efficacy of Tai Chi on lower limb function of Parkinson's disease patients: A systematic review and meta-analysis

Background

At present, the effect of Tai Chi (TC) on lower limb function in patients with Parkinson's disease (PD) is controversial. Therefore, we conducted a meta-analysis on the influence of TC on lower limb function in PD patients.

Methods

According to the PRISMA guidelines, seven databases were searched. Randomized controlled trials (RCTS) were selected and screened according to inclusion and exclusion criteria. We assessed the quality of the studies using the Cochrane Risk of Bias tool and then extracted the characteristics of the included studies. The random effect model was adopted, and heterogeneity was measured by I ² statistic.

Results

A total of 441 articles were screened, and 10 high-quality RCTs were with a total of 532 patients with PD met Our inclusion criteria. Meta-analysis showed that compared To control groups TC improved several outcomes. TC significantly improved motor function (SMD = -0.70; 95% CI = -0.95, -0.45; p < 0.001; I ² = 35%), although The results were not statistically significant for The subgroup analysis of TC duration (SMD = -0.70; 95% CI = -0.95, -0.45; p = 0.88; I ² = 0%;). TC significantly improved balance function (SMD = 0.89; 95% CI = 0.51, 1.27; p < 0.001; I ² = 54%), functional walking capacity (SMD = -1.24; 95% CI = -2.40, -0.09; p = 0.04; I ² = 95%), and gait velocity (SMD = 0.48; 95% CI = -0.02, 0.94; p = 0.04; I ² = 78%), But Did Not improve endurance (SMD = 0.31; 95% CI = -0.12, 0.75; p = 0.16; I ² = 0%), step length (SMD = 0.01; 95% CI = -0.34, 0.37; p = 0.94; I ² = 29%), and cadence (SMD = 0.06; 95% CI = -0.25, 0.36; p = 0.70; I ² = 0%).

Conclusion

TC has beneficial effects on motor function, balance function, functional walking ability, and gait velocity, but does not improve walking endurance, stride length, and cadence.

The Blood–Brain Barrier—A Key Player in Multiple Sclerosis Disease Mechanisms

Over the past decade, multiple sclerosis (MS), a chronic neuroinflammatory disease with severe personal and social consequences, has undergone a steady increase in incidence and prevalence rates worldwide. Despite ongoing research and the development of several novel therapies, MS pathology remains incompletely understood, and the prospect for a curative treatment continues to be unpromising in the near future. A sustained research effort, however, should contribute to a deeper understanding of underlying disease mechanisms, which will undoubtedly yield improved results in drug development. In recent years, the blood–brain barrier (BBB) has increasingly become the focus of many studies as it appears to be involved in both MS disease onset and progression. More specifically, neurovascular unit damage is believed to be involved in the critical process of CNS immune cell penetration, which subsequently favors the development of a CNS-specific immune response, leading to the classical pathological and clinical hallmarks of MS. The aim of the current narrative review is to merge the relevant evidence on the role of the BBB in MS pathology in a comprehensive and succinct manner. Firstly, the physiological structure and functions of the BBB as a component of the more complex neurovascular unit are presented. Subsequently, the authors review the specific alteration of the BBB encountered in different stages of MS, focusing on both the modifications of BBB cells in neuroinflammation and the CNS penetration of immune cells. Finally, the currently accepted theories on neurodegeneration in MS are summarized.

Mechanisms of motor symptom improvement by long-term Tai Chi training in Parkinson’s disease patients

Background

Tai Chi has been shown to improve motor symptoms in Parkinson’s disease (PD), but its long-term effects and the related mechanisms remain to be elucidated. In this study, we investigated the effects of long-term Tai Chi training on motor symptoms in PD and the underlying mechanisms.

Methods

Ninety-five early-stage PD patients were enrolled and randomly divided into Tai Chi (n = 32), brisk walking (n = 31) and no-exercise (n = 32) groups. At baseline, 6 months and 12 months during one-year intervention, all participants underwent motor symptom evaluation by Berg balance scale (BBS), Unified PD rating-scale (UPDRS), Timed Up and Go test (TUG) and 3D gait analysis, functional magnetic resonance imaging (fMRI), plasma cytokine and metabolomics analysis, and blood Huntingtin interaction protein 2 (HIP2) mRNA level analysis. Longitudinal self-changes were calculated using repeated measures ANOVA. GEE (generalized estimating equations) was used to assess factors associated with the longitudinal data of rating scales. Switch rates were used for fMRI analysis. False discovery rate correction was used for multiple correction.

Results

Participants in the Tai Chi group had better performance in BBS, UPDRS, TUG and step width. Besides, Tai Chi was advantageous over brisk walking in improving BBS and step width. The improved BBS was correlated with enhanced visual network function and downregulation of interleukin-1β. The improvements in UPDRS were associated with enhanced default mode network function, decreased L-malic acid and 3-phosphoglyceric acid, and increased adenosine and HIP2 mRNA levels. In addition, arginine biosynthesis, urea cycle, tricarboxylic acid cycle and beta oxidation of very-long-chain fatty acids were also improved by Tai Chi training.

Conclusions

Long-term Tai Chi training improves motor function, especially gait and balance, in PD. The underlying mechanisms may include enhanced brain network function, reduced inflammation, improved amino acid metabolism, energy metabolism and neurotransmitter metabolism, and decreased vulnerability to dopaminergic degeneration.

Trial registration This study has been registered at Chinese Clinical Trial Registry (Registration number: ChiCTR2000036036; Registration date: August 22, 2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40035-022-00280-7.

Involvement of Astrocytes and microRNA Dysregulation in Neurodegenerative Diseases: From Pathogenesis to Therapeutic Potential

Astrocytes are the most widely distributed and abundant glial cells in the central nervous system (CNS). Neurodegenerative diseases (NDDs) are a class of diseases with a slow onset, progressive progression, and poor prognosis. Common clinical NDDs include Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD). Although these diseases have different etiologies, they are all associated with neuronal loss and pathological dysfunction. Accumulating evidence indicates that neurotransmitters, neurotrophic factors, and toxic metabolites that are produced and released by activated astrocytes affect and regulate the function of neurons at the receptor, ion channel, antigen transfer, and gene transcription levels in the pathogenesis of NDDs. MicroRNAs (miRNAs) are a group of small non-coding RNAs that play a wide range of biological roles by regulating the transcription and post-transcriptional translation of target mRNAs to induce target gene expression and silencing. Recent studies have shown that miRNAs participate in the pathogenesis of NDDs by regulating astrocyte function through different mechanisms and may be potential targets for the treatment of NDDs. Here, we review studies of the role of astrocytes in the pathogenesis of NDDs and discuss possible mechanisms of miRNAs in the regulation of astrocyte function, suggesting that miRNAs may be targeted as a novel approach for the treatment of NDDs.

Study on antrodia camphorata polysaccharide in alleviating the neuroethology of PD mice by decreasing the expression of NLRP3 inflammasome

Parkinson's disease (PD) is a neurodegenerative disease, and the role of neuroinflammation in the pathogenesis and progression of PD has been confirmed. The polysaccharides and triterpenoids of antrodia camphorata (a polyporous fungus) harbor diverse and powerful pharmacological effects. In this study, 6-hydroxydopamine was used to construct a PD mouse model. After antrodia camphorata polysaccharide (ACP) intervention, neurobehavioral changes were detected, neurotransmitter changes in striatum were determined by high-performance liquid chromatography, the alterations of striatal NOD-like receptor pyrin domain containing three (NLRP3) were examined by immunohistochemistry, and the expression of NLRP3, IL-1β, Caspase-1, and proCaspase-1 were detected by western blot. To be specific, the items of neurobehavioral test included open field activity, rotary test, pole test, gait analysis, and swimming test. As a result, 6-hydroxydopamine could lead to PD-like lesions, including tremor, stiffness, attenuated spontaneous activity, and bradykinesia in mice, and the expression of tyrosine hydroxylase in the striatum was decreased. After ACP intervention, the neuroethology of mice was significantly improved, as demonstrated by the elevated levels of dopamine in the striatum and the decreased expression of dopamine in the striatum in NLRP3 inflammasome. NLRP3 inflammasome played an important role in neuroinflammation in PD mice. ACP could reduce the activation of NLRP3 and expression of related inflammatory factors.

ECMO attenuates inflammation response and increases ATPase activity in brain of swine model with cardiac arrest compared with CCPR

Extracorporeal membrane oxygenation (ECMO) could increase survival rate and neurological outcomes of cardiac arrest (CA) patients compared with conventional cardiopulmonary resuscitation (CCPR). Currently, the underlying mechanisms how ECMO improves neurological outcomes of CA patients compared with CCPR have not been revealed. A pig model of CA was established by ventricular fibrillation induction and then underwent CCPR or ECMO. Survival and hemodynamics during the 6 h after return of spontaneous circulation (ROSC) were compared. The levels of inflammatory cytokines and Ca²⁺-ATPase and NA⁺-K⁺-ATPase activities were detected. Brain tissues histology and ultra-microstructure in CCPR and ECMO groups were also examined. Results suggested that ECMO significantly improved the survival of pigs compared with CCPR. Heart rate (HR) decreased while cardiac output (CO) increased along with the time after ROSC in both ECMO and CCPR groups. At each time point, HR in ECMO groups was lower than that in CCPR group while CO and mean arterial pressure in ECMO group was higher than CCPR group. In ECMO group, lower levels of IL-1, IL-1β, IL-6, TNFα, and TGFβ, especially IL-1, IL-6, TNFα, and TGFβ, were found compared that in CCPR group while no difference of IL-10 between the two groups was observed. Similar with the results from enzyme-linked immunosorbent assay, decreased expressions of IL-6 and TGFβ were also identified by Western blotting. And Ca²⁺-ATPase and NA⁺-K⁺-ATPase activities were increased by ECMO compared with CCPR. Hematoxylin and eosin staining and ultra-microstructure examination also revealed an improved inflammation situation in ECMO group compared with CCPR group.

Transforming growth factor-beta 1 signaling regulates neuroinflammation and apoptosis in mild traumatic brain injury

Mild traumatic brain injury (mTBI) is a low-level injury, which often remains undiagnosed, and in most cases it leads to death and disability as it advances as secondary injury. Therefore, it is important to study the underlying signaling mechanisms of mTBI-associated neurological ailments. While transforming growth factor-beta1 (TGF-β1) has a significant role in inflammation and apoptosis in myriads of other pathophysiological conditions, the precise function of increased TGF-β1 after mTBI is unknown. In this study, our objective is to study the physiological relevance and associated mechanisms of TGF-β1-mediated inflammation and apoptosis in mTBI. Using an in vitro stretch-injury model in rat neuronal cultures and the in vivo fluid percussion injury (FPI) model in rats, we explored the significance of TGF-β1 activation in mTBI. Our study demonstrated that the activation of TGF-β1 in mTBI correlated with the induction of free radical generating enzyme NADPH oxidase 1 (NOX1). Further, using TGF-β type I receptor (TGF-βRI) inhibitor SB431542 and transfection of TGF-β1 siRNA and TGF-β antagonist Smad7, we established the neuroinflammatory and apoptotic role of TGF-β1 in mTBI. Inhibition of TGF-βRI or TGF-β1 diminished TGF-β1-induced inflammation and apoptosis. Further, the enhanced TGF-β1 activation increased the phosphorylation of R-Smads including Smad2 and Smad3 proteins. By immunofluorescence, western blotting, ELISA and TUNEL experiments, we demonstrated the up-regulation of pro-inflammatory cytokines IL-1β and TNF-α and apoptotic cell death in neurons. In conclusion, this study could establish the significance of TGF-β1 in transforming the pathophysiology of mTBI into secondary injury.

Selective induction of IL-1β after a brief isoflurane anesthetic in children undergoing MRI examination

PURPOSE

To determine if isoflurane anesthesia without surgery causes systemic inflammation in children. Inflammation is targeted as responsible for the development of many neurologic pathologies. The effect will be evaluated by measuring serum cytokine levels before and after isoflurane anesthesia. The possible neurotoxic effect of anesthetic agents is a concern in pediatric anesthesia. Questions remain as to the true effects of anesthesia alone on systemic inflammation. The current study assesses systemic inflammatory response to general anesthesia in children not exposed to surgical stress.

METHODS

Twenty-five patients, aged 6 months to 11 years undergoing MRI scanning were recruited. Patients with ASA Physical Status Classification >II, known neurologic disease, prematurity, recent infection, or current treatment with anti-inflammatory medications were excluded. Each patient received a sevoflurane induction, peripheral intravenous catheterization, and laryngeal mask airway placement. Isoflurane was titrated to ensure adequate depth of anesthesia. Two peripheral blood samples were obtained: one immediately after placement of the PIV and one upon arrival to the post-anesthesia care unit. Serum cytokine levels were compared between pre- and post-isoflurane time points using paired t tests.

RESULTS

For all patients, interleukin-1β increased after isoflurane when compared to pre-isoflurane samples (pre = 25.97 ± 9.01, post = 38.53 ± 16.56, p = 0.0002). Serum levels of IL-6 (pre = 2.28 ± 2.27, post = 2.04 ± 2.15, p = 0.146) and tumor necrosis factor-α (pre = 94.26 ± 18.07, post = 85.84 ± 12.12, p = 0.057) were not significantly changed. Interleukin-10 and vascular endothelial growth factor were undetectable in pre- and post-isoflurane samples at a minimum detection threshold of 6.6 and 10 pg/ml, respectively.

CONCLUSIONS

A brief (approximately 60 min) exposure to isoflurane general anesthesia, without induced surgical stress, significantly increased serum IL-1β, a selective activation marker of systemic inflammation (IL-1β pathway).