Astragalus polysaccharide alleviates cognitive impairment and β-amyloid accumulation in APP/PS1 mice via Nrf2 pathway

Neurodevelopmental changes in Drosophila melanogaster are restored by treatment with lutein-loaded nanoparticles: Positive modulation of neurochemical and behavioral parameters

Neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), are characterized by persistent changes in communication and social interaction, as well as restricted and stereotyped patterns of behavior. The complex etiology of these disorders possibly combines the effects of multiple genes and environmental factors. Hence, exposure to insecticides such as imidacloprid (IMI) has been used to replicate the changes observed in these disorders. Lutein is known for its anti-inflammatory and antioxidant properties and is associated with neuroprotective effects. Therefore, the aim of this study was to evaluate the protective effect of lutein-loaded nanoparticles, along with their mechanisms of action, on Drosophila melanogaster offspring exposed to IMI-induced damage. To simulate the neurodevelopmental disorder model, flies were exposed to a diet containing IMI for 7 days. Posteriorly, their offspring were exposed to a diet containing lutein-loaded nanoparticles for a period of 24 h, and male and female flies were subjected to behavioral and biochemical evaluations. Treatment with lutein-loaded nanoparticles reversed the parameters of hyperactivity, aggressiveness, social interaction, repetitive movements, and anxiety in the offspring of flies exposed to IMI. It also protected markers of oxidative stress and cell viability, in addition to preventing the reduction of Nrf2 and Shank3 immunoreactivity. These results demonstrate that the damage induced by exposure to IMI was restored through treatment with lutein-loaded nanoparticles, elucidating lutein's mechanisms of action as a therapeutic agent, which, after further studies, can become a co-adjuvant in the treatment of neurodevelopmental disorders, such as ASD and ADHD.

Efficacy, safety, and response predictors of Astragalus in patients with mild to moderate Alzheimer's disease: A study protocol of an assessor-blind, statistician-blind open-label randomized controlled trial

Background

This pragmatic clinical trial aims to determine the efficacy and safety of add-on Astragalus membranaceus (AM) for cognition and non-cognition in patients with of mild to moderate Alzheimer's disease complicated with orthostatic hypotension in orthostatic hypotension, elucidate the underlying mechanisms, identify related response predictors, and explore effective drug components.

Methods

This is an add-on, assessor-blinded, parallel, pragmatic, randomized controlled trial. At least 66 adults with mild to moderate Alzheimer's disease (AD) and OH aged 50-85 years will be recruited. Participants will be randomized in a 1:1:1 ratio to receive 24 weeks of routine care or add-on low dose AM or add-on high dose AM group. The primary efficacy outcome will be measured by the Alzheimer's Disease Assessment Scale-Cognitive Subscale, Chinese version. Secondary efficacy outcome assessment will include neuropsychological tests, blood pressure, plasma biomarkers, multimodal electroencephalograms, and neuroimaging. Safety outcome measures will include physical examinations, vital signs, electrocardiography, laboratory tests (such as hematologic and blood chemical tests), and adverse event records.

Ethics and dissemination

This trial was approved and supervised by Fujian Medical University Union Hospital (2021KJCX040). Independent results, findings will be published in peer-reviewed journals and presented at national and international conferences.

Trial registration number

NCT05647473; ClinicalTrials.gov Identifier.

Characterization of Phenolic Profile and Biological Properties of Astragalus membranaceus Fisch. ex Bunge Commercial Samples

Astragalus membranaceus Fisch. ex Bunge (syn. Astragalus mongholicus Bunge) is one of the notable medicinal and food plants. Therefore, the aim of this study was to calculate the phenolic composition and antioxidant, antimicrobial, as well as enzyme inhibitory [acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR)] activities with chemometric approaches of the hydromethanolic and water extracts of commercial A. membranaceus samples. Ten individual phenolic compounds were determined using high-performance liquid chromatography (HPLC), and only quercetin was found at a level of above 80 µg/g DW in both extracts. Moreover, the highest antioxidant activity in DPPH, FRAP, ABTS, and CUPRAC assays was found in the sample containing the roots in loose form from USA. A. membranaceus extracts displayed the inhibition zone diameters within the range from 10 to 22 mm antimicrobial activity against S. aureus, while there were no inhibition zones in any extracts in case of E. coli. The extracts of A. membranaceous showed an inhibition rate below 40% against TYR, and among tested extracts, only two samples were able to inhibit BChE with IC50 values of above 30 µg/mL. Correlation analysis showed a highly positive relationship between their phenolic composition and antioxidant activity. Concluding, the obtained results confirmed that A. membranaceus commercial samples could be an important dietary source of natural antioxidants.

Pharmacological effects of Astragalus polysaccharides in treating neurodegenerative diseases

Astragalus membranaceus widely used in traditional Chinese medicine, exhibits multiple pharmacological effects, including immune stimulation, antioxidation, hepatoprotection, diuresis, antidiabetes, anticancer, and expectorant properties. Its main bioactive compounds include flavonoids, triterpene saponins, and polysaccharides. Astragalus polysaccharides (APS), one of its primary bioactive components, have been shown to possess a variety of pharmacological activities, such as antioxidant, immunomodulatory, anti-inflammatory, antitumor, antidiabetic, antiviral, hepatoprotective, anti-atherosclerotic, hematopoietic, and neuroprotective effects. This review provides a comprehensive summary of the molecular mechanisms and therapeutic effects of APS in treating neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). It discusses how APS improve insulin resistance, reduce blood glucose levels, enhance cognitive function, and reduce Aβ accumulation and neuronal apoptosis by modulating various pathways such as Nrf2, JAK/STAT, Toll, and IMD. For PD, APS protect neurons and stabilize mitochondrial function by inhibiting ROS production and promoting autophagy through the PI3K/AKT/mTOR pathway. APS also reduce oxidative stress and neurotoxicity induced by 6-hydroxydopamine, showcasing their neuroprotective effects. In MS, APS alleviate symptoms by suppressing T cell proliferation and reducing pro-inflammatory cytokine expression via the PD-1/PD-Ls pathway. APS promote myelin regeneration by activating the Sonic hedgehog signaling pathway and fostering the differentiation of neural stem cells into oligodendrocytes. This article emphasizes the significant antioxidant, anti-inflammatory, immunomodulatory, and neuroprotective pharmacological activities of APS, highlighting their potential as promising candidates for the treatment of neurodegenerative diseases.

Hypoglycemic TCM formulas (Huangqi-Gegen drug pair) have the potential as an Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a neurological disorder. There is a considerable unmet medical need among those suffering from it.

HYPOTHESIS AND PURPOSE

Given the link between type-2 diabetes mellitus (T2DM) and AD, hypoglycemic traditional Chinese medicine formulas (TCMFs) may be a treatment for AD. We investigated the possibility of identifying anti-AD medicines in hypoglycemic TCMFs and presented another option for the screening of AD medications.

STUDY DESIGN AND METHODS

Paralysis of the transgenic Caenorhabditis elegans (C. elegans) strain CL4176 (caused by amyloid beta (Aβ)1-42 aggregates) was used to evaluate the anti-AD effect. The toxicity and neurodegeneration induced by neuronal expression of Aβ in the transgenic C. elegans strain CL2355 were determined using a 5-hydroxytryptamine (5-HT) assay. The transgenic Aβ-expressing strain CL 2006 and transgenic tau-expressing strain BR5270 were used to explore the effect of TCMFs on protein expression in C. elegans using ELISAs. Then, network pharmacology was used to determine the mechanism of action. The Traditional Chinese Medicine Inheritance Support System platform was used to investigate prescription patterns, core drugs, and optimum combinations of hypoglycemic TCMFs for AD.

RESULTS

Sixteen hypoglycemic TCMFs prolonged the PT50 (half paralysis time) of the CL4176 strain of C. elegans, reduced the percentage of worms paralyzed. The results of network pharmacology showed that prostaglandin-endoperoxide synthase 2 (PTGS2) and acetylcholine esterase (AChE) are main targets of hypoglycemic TCMFs. Enriched pathway analysis showed that the cholinergic receptor-related pathway was the core pathway of hypoglycemic TCMFs. According to the "four qi and five flavors" system of TCM theory, the main pharmacological qualities were "cold" and "sweet." Through the analysis by TCMISS, we found that Huangqi-Gegen drug pair as the significant Chinese herbs of hypoglycemic TCMFs. The Huangqi-Gegen pairing had the most robust therapeutic effect when delivered at a 2:1 (v/v) ratio. It reduced the paralysis caused by 5-HT, decreased protein expression of AChE and PTGS2, and reduced Aβ deposition in the brain of the CL2006 strain of C. elegans.

CONCLUSIONS

Huangqi-Gegen is a promising treatment of AD, and its mechanism may be induced by suppressing the protein production of AChE and PTGS2, reducing 5-HT intake, and then decreasing Aβ deposition.

The role of Nrf2 signaling pathways in nerve damage repair

The protein, Nuclear factor-E2-related factor 2 (Nrf2), is a transitory protein that acts as a transcription factor and is involved in the regulation of many cytoprotective genes linked to xenobiotic metabolism and antioxidant responses. Based on the existing clinical and experimental data, it can be inferred that neurodegenerative diseases are characterized by an excessive presence of markers of oxidative stress (OS) and a reduced presence of antioxidant defense systems in both the brain and peripheral tissues. The presence of imbalances in the homeostasis between oxidants and antioxidants has been recognized as a substantial factor in the pathogenesis of neurodegenerative disorders. The dysregulations include several cellular processes such as mitochondrial failure, protein misfolding, and neuroinflammation. These dysregulations all contribute to the disruption of proteostasis in neuronal cells, leading to their eventual mortality. A noteworthy component of Nrf2, as shown by recent research undertaken over the last decade, is to its role in the development of resistance to OS. Nrf2 plays a pivotal role in regulating systems that defend against OS. Extant research offers substantiation for the protective and defensive roles of Nrf2 in the context of neurodegenerative diseases. The purpose of this study is to provide a comprehensive analysis of the influence of Nrf2 on OS and its function in regulating antioxidant defense systems within the realm of neurodegenerative diseases. Furthermore, we evaluate the most recent academic inquiries and empirical evidence about the beneficial and potential role of certain Nrf2 activator compounds within the realm of therapeutic interventions.

Research on the signaling pathways related to the intervention of traditional Chinese medicine in Parkinson's disease:A literature review

ETHNOPHARMACOLOGICAL RELEVANCE

Parkinson's disease (PD) is the most common progressive neurodegenerative disorder affecting more than 10 million people worldwide and is characterized by the progressive loss of Daergic (DA) neurons in the substantia nigra pars compacta. It has been reported that signaling pathways play a crucial role in the pathogenesis of PD, while the active ingredients of traditional Chinese medicine (TCM) have been found to possess a protective effect against PD. TCM has demonstrated significant potential in mitigating oxidative stress (OS), neuroinflammation, and apoptosis of DA neurons via the regulation of signaling pathways associated with PD.

AIM OF THE REVIEW

This study discussed and analyzed the signaling pathways involved in the occurrence and development of PD and the mechanism of active ingredients of TCM regulating PD via signaling pathways, with the aim of providing a basis for the development and clinical application of therapeutic strategies for TCM in PD.

MATERIALS AND METHODS

With "Parkinson's disease", "Idiopathic Parkinson's Disease", "Lewy Body Parkinson's Disease", "Parkinson's Disease, Idiopathic", "Parkinson Disease, Idiopathic", "Parkinson's disorders", "Parkinsonism syndrome", "Traditional Chinese medicine", "Chinese herbal medicine", "active ingredients", "medicinal plants" as the main keywords, PubMed, Web of Science and other online search engines were used for literature retrieval.

RESULTS

PD exhibits a close association with various signaling pathways, including but not limited to MAPKs, NF-κB, PI3K/Akt, Nrf2/ARE, Wnt/β-catenin, TLR/TRIF, NLRP3, Notch. The therapeutic potential of TCM lies in its ability to regulate these signaling pathways. In addition, the active ingredients of TCM have shown significant effects in improving OS, neuroinflammation, and DA neuron apoptosis in PD.

CONCLUSION

The active ingredients of TCM have unique advantages in regulating PD-related signaling pathways. It is suggested to combine network pharmacology and bioinformatics to study the specific targets of TCM. This not only provides a new way for the prevention and treatment of PD with the active ingredients of TCM, but also provides a scientific basis for the selection and development of TCM preparations.

Structural identification and anti-neuroinflammatory effect of a heteropolysaccharide ATP50-3 from Acorus tatarinowii rhizome

Acorus tatarinowii, a famous traditional Chinese medicine, is used for the clinical treatment of memory impairment and dementia. In this research, AT50, the crude polysaccharide extracted from A. tatarinowii rhizome, significantly improved the memory and learning ability of mice with Alzheimer's disease (AD) and exerted excellent anti-neuroinflammatory effects. More importantly, AT50 returned the levels of NO, TNF-α, IL-1β, PGE-2, and IL-6 in AD mouse brains to normal levels. To identify the active ingredients in AT50, a heteropolysaccharide ATP50-3 was obtained from AT50. Structural analysis indicated ATP50-3 consisted of α-L-Araf-(1→, →2)-α-L-Araf-(1→, →3)-α-L-Araf-(1→, →5)-α-L-Araf-(1→, α-D-Xylp-(1→, →3,4)-β-D-Xylp-(1→, →3)-α-D-Galp-(1→, →3,6)-α-D-Galp-(1→, →6)-4-OAc-α-D-Galp-(1→, →3,4,6)-α-D-Galp-(1→, →4)-α-D-Glcp-(1→, →2,3,6)-β-D-Glcp-(1→, →4,6)-α-D-Manp-(1→, →3,4)-α-L-Rhap-(1→, →4)-α-D-GalpA-(1→, and →4)-α-D-GlcpA-(1 → residues and terminated with Xyl and Ara. Additionally, ATP50-3 significantly inhibited the release of proinflammatory factors in lipopolysaccharide-stimulated BV2 cells. ATP50-3 may be an active constituent of AT50, responsible for its anti-neuroinflammatory effects, with great potential to treat AD.

Along the microbiota-gut-brain axis: Use of plant polysaccharides to improve mental disorders

With the development of gut microbiota-specific interventions for mental disorders, the interactions between plant polysaccharides and microbiota in the intestinal and their consequent effects are becoming increasingly important. In this review, we discussed the role of plant polysaccharides in improving various mental disorders via the microbiota-gut-brain axis. The chemical and structural characteristics and metabolites of these plant polysaccharides were summarised. Plant polysaccharides and their metabolites have great potential for reshaping gut microbiota profiles through gut microbiota-dependent fermentation. Along the microbiota-gut-brain axis, the consequent pharmacological processes that lead to the elimination of the symptoms of mental disorders include 1) regulation of the central monoamine neurotransmitters, amino acid transmitters and cholinergic signalling system; 2) alleviation of central and peripheral inflammation mainly through the NLRP3/NF-κB-related signalling pathway; 3) inhibition of neuronal apoptosis; and 4) enhancement of antioxidant activities. According to this review, monosaccharide glucose and structure -4-α-Glcp-(1→ are the most potent compositions of the most reported plant polysaccharides. However, the causal structure-activity relationship remains to be extensively explored. Moreover, mechanistic elucidation, safety verification, and additional rigorous human studies are expected to advance plant polysaccharide-based product development targeting the microbiota-gut-brain axis for people with mental disorders.

Neuroprotective effects of Rehmannia glutinosa polysaccharide on chronic constant light (CCL)-induced oxidative stress and autophagic cell death via the AKT/mTOR pathway in mouse hippocampus and HT-22 cells

Rehmannia glutinosa polysaccharide (RGP) has been reported to exhibit anti-anxiety effects, yet the underlying mechanism remains unclear. Chronic constant light (CCL) induced cognitive dysfunction associated with oxidative stress in mice has been reported. Here, the neuroprotective effect of RGP on hippocampal neuron damage in CCL-treated mice was investigated. In vivo study, mice were subjected to CCL for 4 weeks and/or oral administration of 100, 200 and 400 mg/kg RGP every other day. In vitro experiment, hippocampal neuron cells (HT-22) was exposed to LED light and/or supplemented with 62.5, 125 and 250 μg/mL RGP. Mice exposed to CCL showed impaired cognitive and depressive-like behavior in the hippocampus, which were reversed by RGP. Meanwhile, RGP reversed light-induced oxidative stress and autophagy both in mice and hippocampal neuron cells (HT-22). Furthermore, compared with Light-exposed group, RGP treatment activated the AKT/mTOR pathway. Importantly, the AKT inhibitor Perifosine significantly weakened the neuroprotective of RGP on Light-induced oxidative stress and autophagy in HT-22 cells by inhibiting AKT/mTOR pathway and increasing the content of autophagy-related protein. Our data demonstrated, for the first time, that oxidative stress and the AKT/mTOR pathway plays a critical role in Light-induced apoptosis and autophagic cell death in mice and HT-22 cells.

Astragalus polysaccharides ameliorate epileptogenesis, cognitive impairment, and neuroinflammation in a pentylenetetrazole-induced kindling mouse model

Background: Epilepsy is a prevalent neurological disease where neuroinflammation plays a significant role in epileptogenesis. Recent studies have suggested that Astragalus polysaccharides (APS) have anti-inflammatory properties, which make them a potential candidate for neuroprotection against central nervous system disease. Nevertheless, the extent of their effectiveness in treating epilepsy remains enigmatic. Therefore, our study aims to investigate the potential of APS to mitigate epileptogenesis and its comorbidities by exploring its underlying mechanism. Methods: Initially, we employed pentylenetetrazol-induced seizure mice to validate APS' effectiveness. Subsequently, we employed network pharmacology analysis to probe the possible targets and signaling pathways of APS in treating epilepsy. Ultimately, we verified the key targets and signaling pathways experimentally, predicting their mechanisms of action. Results: APS have been observed to disturb the acquisition process of kindling, leading to reduced seizure scores and a lower incidence of complete kindling. Moreover, APS has been found to improve cognitive impairments and prevent hippocampal neuronal damage during the pentylenetetrazole (PTZ)-kindling process. Subsequent network pharmacology analysis revealed that APS potentially exerted their anti-epileptic effects by targeting cytokine and toll-like receptor 4/nuclear factor kappa B (TLR4/NF-κB) signaling pathways. Finally, experimental findings showed that APS efficiently inhibited the activation of astrocytes and reduced the release of pro-inflammatory mediators, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). In addition, APS impeded the activation of the TLR4/NF-κB signaling cascade in a PTZ-induced kindling mouse model. Conclusion: The outcomes of our study suggest that APS exerts an impact on epileptogenesis and mitigates cognitive impairment by impeding neuroinflammatory processes. The mechanism underlying these observations may be attributed to the modulation of the TLR4/NF-κB signaling pathway, resulting in a reduction of the release of inflammatory mediators. These findings partially agree with the predictions derived from network pharmacology analyses. As such, APS represents a potentially innovative and encouraging adjunct therapeutic option for epileptogenesis and cognitive deficit.

Identifying the Anti-inflammatory Effects of Astragalus Polysaccharides in Anti-N-Methyl-D-Aspartate Receptor Encephalitis: Network Pharmacology and Experimental Validation

BACKGROUND

Astragalus polysaccharides (APS), a group of bioactive compounds obtained from the natural source Astragalus membranaceus (AM), exhibits numerous pharmacological actions in the central nervous system, such as anti-inflammatory, antioxidant, and immunomodulatory properties. Despite the remarkable benefits, the effectiveness of APS in treating anti- N-methyl-D-aspartate receptor (NMDAR) encephalitis and the corresponding mechanism have yet to be fully understood. As such, this study aims to investigate the impact of APS on anti-NMDAR encephalitis and explore the potential molecular network mechanism.

METHODS

The impact of APS intervention on mice with anti-NMDAR encephalitis was assessed, and the possible molecular network mechanism was investigated utilizing network pharmacology and bioinformatics techniques such as Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG),protein-protein interaction (PPI) network, and molecular docking. Enzymelinked immunosorbent assay (ELISA) was applied to detect the expression of core target proteins.

RESULTS

APS significantly ameliorated cognitive impairment and reduced susceptibility to PTZinduced seizures in mice with anti-NMDAR encephalitis, confirming the beneficial effect of APS on anti-NMDAR encephalitis. Seventeen intersecting genes were identified between APS and anti- NMDAR encephalitis. GO and KEGG analyses revealed the characteristics of the intersecting gene networks. STRING interaction in the PPI network was applied to find crucial molecules. The results of molecular docking suggested that APS may regulate interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) as potential targets in anti-NMDAR encephalitis. Furthermore, the levels of IL-1β, IL-6, and TNF-α detected by ELISA in anti-NMDAR encephalitis mice were significantly downregulated in response to the administration of APS.

CONCLUSION

The findings of this study demonstrate the significant role of APS in the treatment of anti-NMDAR encephalitis, as it effectively suppresses inflammatory cytokines. These results suggest that APS has the potential to be considered as a viable herbal medication for the treatment of anti-NMDAR encephalitis.

Unveiling the neuroprotective potential of dietary polysaccharides: a systematic review

Central nervous system (CNS) disorders present a growing and costly global health challenge, accounting for over 11% of the diseases burden in high-income countries. Despite current treatments, patients often experience persistent symptoms that significantly affect their quality of life. Dietary polysaccharides have garnered attention for their potential as interventions for CNS disorders due to their diverse mechanisms of action, including antioxidant, anti-inflammatory, and neuroprotective effects. Through an analysis of research articles published between January 5, 2013 and August 30, 2023, encompassing the intervention effects of dietary polysaccharides on Alzheimer's disease, Parkinson's disease, depression, anxiety disorders, autism spectrum disorder, epilepsy, and stroke, we have conducted a comprehensive review with the aim of elucidating the role and mechanisms of dietary polysaccharides in various CNS diseases, spanning neurodegenerative, psychiatric, neurodevelopmental disorders, and neurological dysfunctions. At least four categories of mechanistic bases are included in the dietary polysaccharides' intervention against CNS disease, which involves oxidative stress reduction, neuronal production, metabolic regulation, and gut barrier integrity. Notably, the ability of dietary polysaccharides to resist oxidation and modulate gut microbiota not only helps to curb the development of these diseases at an early stage, but also holds promise for the development of novel therapeutic agents for CNS diseases. In conclusion, this comprehensive review strives to advance therapeutic strategies for CNS disorders by elucidating the potential of dietary polysaccharides and advocating interdisciplinary collaboration to propel further research in this realm.

Jia-Wei-Kai-Xin-San Treatment Alleviated Mild Cognitive Impairment through Anti-Inflammatory and Antiapoptotic Mechanisms in SAMP8 Mice

Background

Alleviating mild cognitive impairment (MCI) is crucial to delay the progression of Alzheimer's disease (AD). Jia-Wei-Kai-Xin-San (JWKXS) is applied for treating AD with MCI. However, the mechanism of JWKXS in the treatment of MCI is unclear. Thus, this study aimed to investigate the effect and mechanism of JWKXS in SAMP8 mice models of MCI.

Methods

MCI models were established to examine learning and memory ability and explore the pathomechanisms in brain of SAMP8 mice at 4, 6, and 8 months. The mice were treated for 8 weeks and the effects of JWKXS on MCI were characterized through Morris water maze and HE/Nissl's/immunohistochemical staining. Its mechanism was predicted by the combination of UPLC-Q-TOF/MS and system pharmacology analysis, further verified with SAMP8 mice, BV2 microglial cells, and PC12 cells.

Results

It was found that 4-month-old SAMP8 mice exhibited MCI. Two months of JWKXS treatment improved the learning and memory ability, alleviated the hippocampal tissue and neuron damage. Through network pharmacology, four key signaling pathways were found to be involved in treatment of MCI by JWKXS, including TLR4/NF-κB pathway, NLRP3 inflammasome activation, and intrinsic and extrinsic apoptosis. In vitro and in vivo experiments demonstrated that JWKXS attenuated neuroinflammation by inhibiting microglia activation, suppressing TLR4/NF-κB and NLRP3 inflammasome pathways, and blocking the extrinsic and intrinsic apoptotic pathways leading to neuronal apoptosis suppression in the hippocampus.

Conclusion

JWKXS treatment improved the learning and memory ability and conferred neuroprotective effects against MCI by inducing anti-inflammation and antiapoptosis. Limitations. The small sample size and short duration of the intervention limit in-depth investigation of the mechanisms. Future Prospects. This provides a direction for further clarification of the anti-AD mechanism, and provides certain data support for the formulation to move toward clinical practice.

Polysaccharide from Paris polyphylla improves learning and memory ability in D-galactose-induced aging model mice based on antioxidation, p19/p53/p21, and Wnt/β-catenin signaling pathways

The current study aimed to investigate the effects and mechanisms of Paris polyphylla polysaccharide component 1 (PPPm-1) to improve learning and memory in D-galactose-induced aging model mice. We determined the effects of PPPm-1 on the brain, organ index, and behavior in the aging model mice induced by D-galactose to study learning and memory improvement. UV-Vis spectrophotometry helped determine the PPPm-1 effect on antioxidant parameters associated with learning and memory in the brain and related organs of aging mice. Moreover, in the hippocampi of aging model mice, PPPm-1 effect on the mRNA and protein expressions of p19, p53, p21, P16, Rb, Wnt/1, β-catenin, CyclinD1, TCF-4, and GSK-3β were detected using the quantitative real-time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. The results indicated that PPPm-1 could increase the brain and organ indexes, the avoidance latency, the total distance and average speed in the water maze, and the SOD and GSH-PX activities in the brain, liver tissues, and plasma. Moreover, the mRNA and protein expressions of Wnt/1, β-catenin, CyclinD1, and TCF-4 were also elevated in the hippocampi of aging model mice. However, the error times in step-through tests, the MDA content in the brain and liver tissues, the AChE activity in the brain tissue, the protein expressions of P16, Rb in the hippocampi, and the mRNA and protein expressions of p19, p53, p21, and GSK-3β in the hippocampi of aging model mice were significantly decreased. Thus, PPPm-1 significantly enhanced the learning and memory impairment induced by D-galactose in mice. The action mechanisms were associated with anti-oxidative stress, cholinergic nervous system function regulation, LTP enhancement in long-term memory, down-regulated expression of p19/p53/p21 signaling pathway factors, and Wnt/β-catenin signaling pathway activation.

Tbx2 knockdown alleviated sevoflurane-induced cognitive disorder and neuron damages in aged rats via suppressing oxidative stress and ferroptosis

Anesthesia with sevoflurane contributes to perioperative neurocognitive disorder (PND), which is characterized by the deficiency in study and memory. T-Box transcription factor 2 (Tbx2), which is involved in the development of hippocampus neurons, was upregulated in the hippocampus of rats exposed to sevoflurane. Our study aimed to explore the role of Tbx2 in sevoflurane-induced cognitive disorder and hippocampus neuron damages. The expression of Tbx2 in hippocampus was upregulated after sevoflurane exposure, which was accompanied by the accumulation of reactive oxygen species and lipid peroxidation, as well as the loss of neurons in hippocampus. In vitro, silencing Tbx2 suppressed oxidative stress and ferroptosis induced by sevoflurane, whereas exogenous overexpression of Tbx2 exacerbated these processes. Importantly, Tbx2 knockdown improved sevoflurane-induced cognitive disorder in aged rats, as evidenced by the increases in behavioral indexes. Mechanistically, the expression of brain-derived neurotrophic factor (BDNF), as well as the downstream nuclear factor erythroid 2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) signaling, was repressed by Tbx2. Mimicking the activation of BDNF with 7,8-dihydroxyflavone rescued the effects of Tbx2 overexpression on oxidative stress and ferroptosis in vitro, indicating that the BDNF/Nrf2/HO-1 signaling may mediate the role of Tbx2 in sevoflurane-induced cognitive disorder and neuron damages. In summary, Tbx2 may contribute to neuronal damages via enhancing the oxidative stress and ferroptosis caused by sevoflurane. BDNF/Nrf2/HO-1 signaling mediates the role of Tbx2 in sevoflurane-induced cognitive disorder. Knockdown of Tbx2 improves sevoflurane-induced cognitive impairment. Our finding provides a novel insight for PND treatment.

Constituent isoflavones of Puerariae radix as a potential neuroprotector in cognitive impairment: Evidence from preclinical studies

With the increasing aging population worldwide, the incidence of senile cognitive impairment (CI) is increasing, posing a serious threat to the health of elderly persons. Despite developing new drugs aimed at improving CI, progress in this regard has been insufficient. Natural preparations derived from plants have become an unparalleled resource for developing new drugs. Puerariae radix (PR) has a long history as Chinese herbal medicine. PR is rich in various chemical components such as isoflavones, triterpenes, and saponins. The isoflavones (puerarin, daidzein, formononetin, and genistein) exhibit potential therapeutic effects on CI through multiple mechanisms. Relevant literature was organized from major scientific databases such as PubMed, Elsevier, SpringerLink, ScienceDirect, and Web of Science. Using "Puerariae radix," "Pueraria lobata," "isoflavones," "puerarin," "antioxidant," "daidzein," "formononetin," "genistein," "Alzheimer"s disease," and "vascular cognitive impairment" as keywords, the relevant literature was extracted from the databases mentioned above. We found that isoflavones from PR have neuroprotective effects on multiple models of CI via multiple targets and mechanisms. These isoflavones prevent Aβ aggregation, inhibit tau hyperphosphorylation, increase cholinergic neurotransmitter levels, reduce neuroinflammation and oxidative stress, improve synaptic plasticity, promote nerve regeneration, and prevent apoptosis. PR has been used as traditional Chinese herbal medicine for a long time, and its constituent isoflavones exert significant therapeutic effects on CI through various neuroprotective mechanisms. This review will contribute to the future development of isoflavones present in PR as novel drug candidates for the clinical treatment of CI.

Cognitive protection of sinomenine in type 2 diabetes mellitus through regulating the EGF/Nrf2/HO-1 signaling, the microbiota-gut-brain axis, and hippocampal neuron ferroptosis

Recent years have witnessed a growing research interest in traditional Chinese medicine as a neuroprotective nutrient in the management of diabetic cognitive dysfunction. However, the underlying molecular mechanisms of sinomenine in mediating ferroptosis of hippocampal neurons have been poorly understood. This study sought to decipher the potential effect and molecular mechanism of sinomenine in the cognitive dysfunction following type 2 diabetes mellitus (T2DM). Multi-omics analysis was conducted to identify the microbiota-gut-brain axis in T2DM patient samples obtained from the publicly available database. In HT-22 cells, erastin was utilized to create a ferroptosis model, and streptozotocin was injected intraperitoneally to create a rat model of DM. It was noted that intestinal flora imbalance occurred in patients with T2DM-associated cognitive dysfunction. Sinomenine could reduce Erastin-induced hippocampus neuronal ferroptosis by increasing EGF expression. EGF protected hippocampal neurons against ferroptosis by activating the Nrf2/HO-1 signaling pathway. Furthermore, in vivo results confirmed that sinomenine blocked ferroptosis of hippocampal neurons and alleviated cognitive dysfunction in T2DM rats. Collectively, these results suggest that sinomenine confers neuroprotective effects by curtailing hippocampal neuron ferroptosis via the EGF/Nrf2/HO-1 signaling and microbiota-gut-brain axis. It may be a candidate for the treatment of diabetic cognitive dysfunction.

The Potential of Edible and Medicinal Resource Polysaccharides for Prevention and Treatment of Neurodegenerative Diseases

As natural medicines in complementary and alternative medicine, edible and medicinal resources are being gradually recognized throughout the world. According to statistics from the World Health Organization, about 80% of the worldwide population has used edible and medicinal resource products to prevent and treat diseases. Polysaccharides, one of the main effective components in edible and medicinal resources, are considered ideal regulators of various biological responses due to their high effectiveness and low toxicity, and they have a wide range of possible applications for the development of functional foods for the regulation of common, frequently occurring, chronic and severe diseases. Such applications include the development of polysaccharide products for the prevention and treatment of neurodegenerative diseases that are difficult to control by a single treatment, which is of great value to the aging population. Therefore, we evaluated the potential of polysaccharides to prevent neurodegeneration by their regulation of behavioral and major pathologies, including abnormal protein aggregation and neuronal damage caused by neuronal apoptosis, autophagy, oxidative damage, neuroinflammation, unbalanced neurotransmitters, and poor synaptic plasticity. This includes multi-target and multi-pathway regulation involving the mitochondrial pathway, MAPK pathway, NF-κB pathway, Nrf2 pathway, mTOR pathway, PI3K/AKT pathway, P53/P21 pathway, and BDNF/TrkB/CREB pathway. In this paper, research into edible and medicinal resource polysaccharides for neurodegenerative diseases was reviewed in order to provide a basis for the development and application of polysaccharide health products and promote the recognition of functional products of edible and medicinal resources.

Advances in Plant Polysaccharides as Antiaging Agents: Effects and Signaling Mechanisms

Aging refers to the gradual physiological changes that occur in an organism after reaching adulthood, resulting in senescence and a decline in biological functions, ultimately leading to death. Epidemiological evidence shows that aging is a driving factor in the developing of various diseases, including cardiovascular diseases, neurodegenerative diseases, immune system disorders, cancer, and chronic low-grade inflammation. Natural plant polysaccharides have emerged as crucial food components in delaying the aging process. Therefore, it is essential to continuously investigate plant polysaccharides as potential sources of new pharmaceuticals for aging. Modern pharmacological research indicates that plant polysaccharides can exert antiaging effects by scavenging free radicals, increasing telomerase activity, regulating apoptosis, enhancing immunity, inhibiting glycosylation, improving mitochondrial dysfunction regulating gene expression, activating autophagy, and modulating gut microbiota. Moreover, the antiaging activity of plant polysaccharides is mediated by one or more signaling pathways, including IIS, mTOR, Nrf2, NF-κB, Sirtuin, p53, MAPK, and UPR signaling pathways. This review summarizes the antiaging properties of plant polysaccharides and signaling pathways participating in the polysaccharide-regulating aging process. Finally, we discuss the structure-activity relationships of antiaging polysaccharides.

Regulation and mechanism of Astragalus polysaccharide on ameliorating aging in Drosophila melanogaster

Astragalus polysaccharide (APS) is a notable bioactive component of Astragalus membranaceus and has been extensively investigated for its pharmacological activities, including antioxidant, neuroprotection, and anticancer effects. However, the beneficial effects and mechanisms of APS on anti-aging diseases remain largely unknown. Here, we utilized the classic model organism Drosophila melanogaster to investigate the beneficial effects and mechanism of APS on aging-related intestinal homeostasis imbalance, sleeping disorders, and neurodegenerative diseases. The results showed that administration of APS significantly attenuated age-associated disruption of the intestinal barrier, loss of gastrointestinal acid-base balance, reduction in intestinal length, overproliferation of the intestinal stem cells (ISCs), and sleeping disorders upon aging. Furthermore, APS supplementation delayed the onset of Alzheimer's phenotypes in Aβ42-induced Alzheimer's disease (AD) flies, including the extension of lifespan and the increase in motility, but without rescuing neurobehavioral deficits in the AD model of taupathy and Parkinson's disease (PD) model of Pink1 mutation. In addition, transcriptomics was used to dissect updated mechanisms of APS on anti-aging, such as JAK-STAT signaling, Toll signaling, and IMD signaling pathways. Taken together, these studies indicate that APS plays a beneficial role in modulating aging-related diseases, thereby as a potential natural drug to delay aging.

Anti-Aging of the Nervous System and Related Neurodegenerative Diseases With Chinese Herbal Medicine

Human beings have always pursued a prolonged lifespan, while the aging of the nervous system is associated with a large variety of diseases. Pathological aging of the nervous system results in a series of neurodegenerative diseases and can cause disability and death in the elderly. Therefore, there is an urgent need for the prevention and treatment of nervous system aging. Chinese herbal medicines have a long history, featuring rich and safe ingredients, and have great potential for the development of anti-aging treatment. We searched the publications on PubMed with key words "anti-aging of the nervous system" and "Chinese herbal medicine" in recent 10 years, and found sixteen Chinese herbal medicines. Then by comparing their popularity of use as well as active components based on the research articles, five common Chinese herbal medicines namely Ginseng Radix, Lycii Fructus, Astragali Radix, Coptidis Rhizoma and Ginkgo Folium, were confirmed to be the most related to anti-nervous system aging and neural degenerative diseases. At the same time, the active ingredients, research models, action mechanisms and curative effects of these five common Chinese herbal medicines were reviewed. From the five common Chinese herbal medicines reviewed in this paper, many encouraging effects of Chinese herbal medicines on treating nervous system aging and related diseases were revealed and more potent herbs would be explored with the help of the proposed possible mechanisms.

Advances in health-promoting effects of natural polysaccharides: Regulation on Nrf2 antioxidant pathway

Natural polysaccharides (NPs) possess numerous health-promoting effects, such as liver protection, kidney protection, lung protection, neuroprotection, cardioprotection, gastrointestinal protection, anti-oxidation, anti-diabetic, and anti-aging. Nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant pathway is an important endogenous antioxidant pathway, which plays crucial roles in maintaining human health as its protection against oxidative stress. Accumulating evidence suggested that Nrf2 antioxidant pathway might be one of key regulatory targets for the health-promoting effects of NPs. However, the information concerning regulation of NPs on Nrf2 antioxidant pathway is scattered, and NPs show different regulatory behaviors in their different health-promoting processes. Therefore, in this article, structural features of NPs having regulation on Nrf2 antioxidant pathway are overviewed. Moreover, regulatory effects of NPs on this pathway for health-promoting effects are summarized. Furthermore, structure-activity relationship of NPs for health-promoting effects by regulating the pathway is preliminarily discussed. Otherwise, the prospects on future work for regulation of NPs on this pathway are proposed. This review is beneficial to well-understanding of underlying mechanisms for health-promoting effects of NPs from the view angle of Nrf2 antioxidant pathway, and provides a theoretical basis for the development and utilization of NPs in promoting human health.

Astragalus species: Phytochemistry, biological actions and molecular mechanisms underlying their potential neuroprotective effects on neurological diseases

Neurodegenerative and neuropsychiatric illnesses are prevalent and life-threatening disorders characterized by a wide range of clinical syndromes and comorbidities, all of which have complex origins and share common molecular pathomechanisms. Although the pathophysiology of neurological illnesses is not completely understood, researchers have discovered that several ion channels and signalling pathways may have played a role in disease pathogenesis. Active substances from Astragalus sp. are being employed for nutrition, and their usefulness in the treatment of neurological illnesses is receiving more attention. Because their extracts and active components exert different pharmacological effects on a variety of ailments, they have a long history of usage as a cure for various diseases. This review summarizes the research work on Astragalus and their biologically active constituents as potential candidates for the protection against and treatment of neurodegenerative and neuropsychiatric disorders to show the potential efficacy of Astragalus sp. and its active ingredients in treating some neurological diseases. Simultaneously, the chemical structures of these active compounds, their sources, biological properties, and mechanisms are also listed. In ethnopharmacological applications, Astragalus membranaceus and spinosus have been studied as traditional medicines worldwide. The chemical constituents of Astragalus species mainly comprise terpenoids, flavonoids, and polysaccharides. The extracts and phytochemical compounds of Astragalus species exhibit various pharmacological activities, including antioxidant, anti-inflammatory, anticancer, antitumor, anticonvulsive, immunomodulatory, and other activities. Based on the current literature, we conclude that Astragalus is a promising dietary herb with multiple potential signal modulating applications that mainly include the modulation of neurotransmitters and receptors, anti-inflammatory activities, inhibition of amyloid aggregation, induction of myelin sheath repair and neurogenesis, as well as activation of the signalling pathways relevant to neurological diseases.

Roots of Astragalus propinquus Schischkin Regulate Transmembrane Iron Transport and Ferroptosis to Improve Cerebral Ischemia-Reperfusion Injury

Background

The dried roots of the Astragalus propinquus Schischkin (RAP) plant, as a traditional Chinese medicine, has been widely used to treat stroke, cerebral ischemia, qi deficiency, and hypertension. Buyang Huanwu decoction is traditionally used to treat stroke in China for more than 200 years and has a significant effect on cerebral ischemia, and RAP is monarch medicine of Buyang Huanwu decoction. Therefore, this study was designed to observe the regulatory effect of RAP on transmembrane iron transporters and ferroptosis-related factors in cerebral ischemia-reperfusion injury (CIRI) in rats.

Methods

Middle cerebral artery occlusion (MCAO) was used to block blood flow in the blood supply area of the middle cerebral artery in seventy male SD rats to induce focal CIRI to establish a rat model of CIRI. RAP was administered to explore the regulatory effect of RAP on iron transmembrane transport under the condition of CIRI. The infarct size was measured using 2,3,5-triphenyl-tetrazolium chloride (TTC) staining, the pathological structure of brain tissue was observed by HE staining, and neuronal injury was evaluated by Nissl staining after treatment. Then, changes in the iron transporters ferritin (Fn), ferritin heavy chain (FHC), ferritin light chain (FLC), transferrin (Tf), transferrin receptor (TfR), divalent metal transporter 1 (DMT1), L-type calcium channel (LTCC), transient receptor potential canonical 6 (TRPC6), and ferroportin 1 (FPN1) were observed by immunohistochemistry staining (IHC) and Western blotting. The expression of key factors of ferroptosis, including the membrane sodium-dependent cystine/glutamate antiporter System Xc⁻ (System Xc⁻) light chain subunit (XCT) and heavy chain subunit (SLC3A2), glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor (NRF2), heme oxygenase-1 (HO-1), and iron-responsive element-binding protein 2 (IREB2) in the brain tissues of rats was assessed by Western blotting. RAP decreased the infarct size and neuronal injury after CIRI in rats. Similarly, RAP treatment regulated the expression of iron transporters. As such, RAP was able to reduce the expression of Fn, FHC, FLC, Tf, TfR, DMT1, and TRPC6 and increase the expression of FPN1 through a Tf/TfR-independent pathway after CIRI in rats.

Conclusion

RAP stimulation inhibited ferroptosis by regulating the expression of the key ferroptosis factors XCT, SLC3A2, GPX4, NRF2, HO-1, and IREB2. In conclusion, RAP regulates transmembrane iron transport and ferroptosis to improve CIRI.

Signal pathways in the treatment of Alzheimer's disease with traditional Chinese medicine

AIM OF THE REVIEW

This study aimed to reveal the classical signal pathways and important potential targets of traditional Chinese medicine (TCM) for treating Alzheimer's disease (AD), and provide support for further investigation on TCM and its active ingredients.

MATERIALS AND METHODS

Literature survey was conducted using PubMed, Web of Science, Google Scholar, CNKI, and other databases, with "Alzheimer's disease," "traditional Chinese medicine," "medicinal herb," "Chinese herb," and "natural plant" as the primary keywords.

RESULTS

TCM could modulate signal pathways related to AD pathological progression, including NF-κB, Nrf2, JAK/STAT, ubiquitin-proteasome pathway, autophagy-lysosome pathway-related AMPK/mTOR, GSK-3/mTOR, and PI3K/Akt/mTOR, as well as SIRT1 and PPARα pathway. It could regulate crosstalk between pathways through a multitarget, thus maintaining chronic inflammatory interaction balance, inhibiting oxidative stress damage, regulating ubiquitin-proteasome system function, modulating autophagy, and eventually improving cognitive impairment in patients with AD.

CONCLUSION

TCM could be multilevel, multitargeted, and multifaceted to prevent and treat AD. In-depth research on the prevention and treatment of AD with TCM could provide new ideas for exploring the pathogenesis of AD and developing new anti-AD drugs.

Update on new trend and progress of the mechanism of polysaccharides in the intervention of Alzheimer's disease, based on the new understanding of relevant theories: A review

Alzheimer's disease (AD), a neurodegenerative disease with insidious onset and progressive progression, is the main type of dementia. Currently, there is no specific cure for the disease. At the same time, a series of drug developments based on the classic theory, the Aβ cascade hypothesis, have not completed phase III clinical trials, challenging the hypothesis. Polysaccharides obtained from natural products can be used in the treatment of AD, which has attracted academic attention due to its advantages of multi-target, multi-channel, no or modest side effects. The TCM syndrome type of AD is mainly "qi and blood deficiency, kidney essence deficiency", and the medicine is mainly used to replenish qi and blood, kidney and bone marrow. Thus, there has been extensive and in-depth research on polysaccharides obtained from tonic Chinese herbal medicine in China. Based on this background, this paper evaluated the effects and mechanisms of natural polysaccharides on AD by combing and screening English and related literature in recent 5 years and summarized the extraction process and structure-activity relationship of polysaccharides.

GSH-AuNP anti-oxidative stress, ER stress and mitochondrial dysfunction in amyloid-beta peptide-treated human neural stem cells

Amyloid-beta (Aβ) peptides have a role in the pathogenesis of Alzheimer's disease (AD) and are thought to promote oxidative stress, endoplasmic reticulum (ER) stress and mitochondrial deficiency, causing neuronal loss in the AD brain. The potential applications of glutathione conjugated gold nanoparticles (GSH-AuNPs) suggest they might have therapeutic value. Several studies have demonstrated that the effects of nanoparticles could provide protective roles in AD. Here, we showed that GSH-AuNPs mediate the viability of human neural stem cells (hNSCs) with Aβ, which was correlated with decreased caspase 3 and caspase 9. Importantly, hNSCs co-treated with GSH-AuNPs were significantly protected from Aβ-induced oxidative stress, as detected using the DCFH-DA, DHE, and MitoSOX staining assays. Furthermore, hNSCs co-treated with GSH-AuNPs were significantly protected from the Aβ-induced reduction in the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and Nrf2 downstream antioxidant target genes (SOD-1, SOD-2, Gpx, Catalase, and HO-1). In addition, GSH-AuNPs rescued the expression levels of ER stress-associated genes (Bip, CHOP, and ASK1) in Aβ-treated hNSCs. GSH-AuNPs normalized ER calcium and mitochondrial cytochrome c homeostasis in Aβ-treated hNSCs. Furthermore, treatment with GSH-AuNPs restored the levels of ATP, D-loop, mitochondrial mass, basal respiration, ATP-linked reparation, maximal respiration capacity, COX activity, mitochondrial membrane potential, and mitochondrial genes (PGC1α, NRF-1 and Tfam) in Aβ-treated hNSCs. Taken together, these findings extend our understanding of the protective effects of GSH-AuNPs against oxidative stress, ER stress and mitochondrial dysfunction in hNSCs with Aβ.

A Review of Traditional Chinese Medicine, Buyang Huanwu Decoction for the Treatment of Cerebral Small Vessel Disease

Cerebral small vessel disease (CSVD) is often referred to as “collaterals disease” in traditional Chinese medicine (TCM), and commonly includes ischemic and hemorrhagic CSVD. TCM has a long history of treating CSVD and has demonstrated unique efficacy. Buyang Huanwu Decoction (BHD) is a classical TCM formula that has been used for the prevention and treatment of stroke for hundreds of years. BHD exerts its therapeutic effects on CSVD through a variety of mechanisms. In this review, the clinical and animal studies on BHD and CSVD were systematically introduced. In addition, the pharmacological mechanisms, active components, and clinical applications of BHD in the treatment of CSVD were reviewed. We believe that an in-depth understanding of BHD, its pharmacological mechanism, disease-drug interaction, and other aspects will help in laying the foundation for its development as a new therapeutic strategy for the treatment of CSVD.

Astragalus mongholicus Bunge (Fabaceae): Bioactive Compounds and Potential Therapeutic Mechanisms Against Alzheimer's Disease

Astragalus mongholicus Bunge (Fabaceae) (also known as Astragali radix-AR), a widely used herb by Traditional Chinese Medicine practitioners, possesses a wide range of pharmacological effects, and has been used to treat Alzheimer's disease (AD) historically. Its bioactive compounds are categorized into four families: saponins, flavonoids, polysaccharides, and others. AR's bioactive compounds are effective in managing AD through a variety of mechanisms, including inhibiting Aβ production, aggregation and tau hyperphosphorylation, protecting neurons against oxidative stress, neuroinflammation and apoptosis, promoting neural stem cell proliferation and differentiation and ameliorating mitochondrial dysfunction. This review aims to shed light upon the chemical constituents of AR and the mechanisms underlying the therapeutic effect of each compound in manging AD. Also presented are clinical studies which reported successful management of AD with AR and other herbs. These will be helpful for drug development and clinical application of AR to treat AD.

Extraction, structure, and activity of polysaccharide from Radix astragali

Radix astragali polysaccharide (RAP) is a water-soluble heteropolysaccharide. It is an immune promoter and regulator, and has antivirus, antitumor, anti-aging, anti-radiation, anti-stress, anti-oxidation and other activitys. The extraction, separation, purification, structure, activity and modification of RAP were summarized. Some extraction methods of RAP had been introduced, and the separation and purification methods of RAP were reviewed, and the structure and activity of RAP were highly discussed. Current derivatization of RAP was outlined. Through the above discussion that the yield of crude polysaccharides from Radix astragali by enzyme-assisted extraction was significantly higher than that by other extraction methods, but each extraction method had different extraction effects under certain conditions, and the activity efficiency of RAP was also different. Therefore, it is particularly important to optimize the extraction method with known better yield for the study of RAP. In addition, the purification and separation of RAP are the key factors affecting the yield and activity of RAP. At the same time, there are still few studies on the derivatiration of Radix astragali polysaccharide, but the researches in this area are very important. RAP also has many important pharmacological effects on human body, but its practical application needs further study. Finally, studies on the structure-activity relationship of RAP still need to be carried out by many scholars. This review would provide some help for further researches on various important applications of RAP.

Astragalus Polysaccharide Relieves Inflammatory Responses in Guinea Pigs with Allergic Rhinitis via Ameliorating NF-kB-Mediated Treg/Th17 Imbalance

BACKGROUND

Allergic rhinitis (AR) is regarded as a prevalent and non-infectious inflammation in nasal mucosa, and astragalus polysaccharide (APS) could mitigate inflammation.

OBJECTIVES

Herein, this study probed the specific mechanism of APS in inflammatory responses in AR.

METHODS

Firstly, AR guinea pig models were established through the stimulation and sensitization of ovalbumin (OVA) and received APS treatment. Changes in nasal symptoms were assessed through counting the sneezing and rubbing times of guinea pigs. The change patterns of OVA-specific immunoglobulin-E (OVA-sIgE), OVA-specific immunoglobulin-G1 (OVA-sIgG1), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in guinea pig serum were identified. Meanwhile, the levels of IL-17, transforming growth factor (TGF)-β, IL-10, and forkhead box protein P3 (Foxp3) in the guinea pig tissues or serum were examined, and CD25⁺Foxp3⁺Treg or CD4⁺IL17⁺Th17 cell proportion was detected. Afterwards, nuclear factor-kappa B (NF-kB) expression in guinea pig nasal mucosa tissues were examined. Rescue experiments were designed to probe the role of NF-kB overexpression in inflammatory responses and Treg/Th17 imbalance in AR guinea pigs.

RESULTS

APS treatment reduced sneezing and rubbing times of AR guinea pigs and suppressed OVA-sIgE, OVA-sIgG1, TNF-α, and IL-6 levels in guinea pig serum, and meanwhile, increased CD25⁺Foxp3⁺Treg cell proportion while reduced CD4⁺IL17⁺Th17 cell proportion in AR guinea pig serum or tissues, in a dose-dependent manner. NF-kB was highly-expressed in AR guinea pigs and down-regulated after APS treatment. NF-kB overexpression facilitated inflammatory responses and Treg/Th17 imbalance in AR.

CONCLUSION

APS reduced Treg/Th17 imbalance via suppressing NF-kB expression, thereby ameliorating inflammatory responses in AR.

Polysaccharides, Next Potential Agent for the Treatment of Epilepsy?

Epilepsy is a chronic neurological disorder. Current pharmacological therapies for epilepsy have limited efficacy that result in refractory epilepsy (RE). Owing to the limitations of conventional therapies, it is needed to develop new anti-epileptic drugs. The beneficial effects of polysaccharides from Chinese medicines, such as Lycium barbarum polysaccharides (COP) and Ganoderma lucidum polysaccharides (GLP), for treatment of epilepsy include regulation of inflammatory factors, neurotransmitters, ion channels, and antioxidant reactions. Especially, polysaccharides could be digested by intestinal microbial flora, referred as “intestinal brain organ” or “adult’s second brain”, may be the target for treatment of epilepsy. Actually, polysaccharides can effectively improve the type and quantity of intestinal flora such as bifidobacteria and lactic acid bacteria and achieve the purpose of treating epilepsy. Therefore, polysaccharides are hypothesized and discussed as potential agent for treatment of epilepsy.

Potential for non-starch polysaccharides in the prevention and remediation of cognitive impairment: A comprehensive review

Non-starch polysaccharides (NSPs) are food ingredients proven to be beneficial in a large number of health issues. However, there is no literature systematic review about the effects and corresponding mechanisms of NSPs on the prevention and remediation of cognitive impairment. In this review, studies on prevention and remediation of NSPs for cognitive deficit caused by diseases, menopause, ageing, chronic stress and environmental pollutants were summarized and the corresponding mechanisms were established. The anti-cognitive deficit effects of NSPs were associated with the modulation of amyloid β (Aβ) deposition, p-Tau aggregation, oxidative stress, inflammation, neuron apoptosis, neurogenesis, neurotransmitters, synaptic plasticity, autophagy and gut microbiota. Although the structure-function relationship has not been elucidated, several structural properties of NSPs such as molecular weight, sulfate content, hydroxyl group content, monosaccharide composition and molecular chain linkage might be crucial for the anti-cognitive deficit property. Notably, this review revealed that NSPs had a positive effect on cognitive impairment and proposed the future perspectives for further research on the anti-cognitive dysfunction effects of NSPs.

All roads lead to Rome - a review of the potential mechanisms by which exerkines exhibit neuroprotective effects in Alzheimer's disease

Age-related neurodegenerative disorders such as Alzheimer’s disease (AD) have become a critical public health issue due to the significantly extended human lifespan, leading to considerable economic and social burdens. Traditional therapies for AD such as medicine and surgery remain ineffective, impractical, and expensive. Many studies have shown that a variety of bioactive substances released by physical exercise (called “exerkines”) help to maintain and improve the normal functions of the brain in terms of cognition, emotion, and psychomotor coordination. Increasing evidence suggests that exerkines may exert beneficial effects in AD as well. This review summarizes the neuroprotective effects of exerkines in AD, focusing on the underlying molecular mechanism and the dynamic expression of exerkines after physical exercise. The findings described in this review will help direct research into novel targets for the treatment of AD and develop customized exercise therapy for individuals of different ages, genders, and health conditions.

Astragalus polysaccharide prevents ferroptosis in a murine model of experimental colitis and human Caco-2 cells via inhibiting NRF2/HO-1 pathway

Ulcerative colitis (UC) is a relapsing and remitting inflammatory bowel disease (IBD), but current conventional drugs lack efficacy. Astragalus polysaccharide (APS) is an active ingredient of Astragalus membranaceus and has been shown to ameliorate experimental colitis. In the present study, we aimed to investigate how APS affects the ferroptosis of intestinal epithelial cells in dextran sulfate sodium (DSS)-induced experimental colitis in mice. Our data showed that APS administration attenuated total weight loss, colon length shortening, disease activity index (DAI) scores, histological damage, and the expression of inflammatory cytokines in the colon of DSS-challenged mice. Moreover, we observed that treatment with APS obviously inhibited ferroptosis in both DSS-challenged mice and RSL3-stimulated Caco-2 cells, as indicated by the decrease in the expression of ferroptosis-associated genes (PTGS2, FTH, and FTL) and the levels of surrogate ferroptosis markers (MDA, GSH, and iron load). Mechanistically, the inhibitory effects of APS on ferroptosis in DSS-challenged mice and RSL3-stimulated Caco-2 cells were associated with the NRF2/HO-1 pathway. Collectively, our findings identify a new role of APS in preventing ferroptosis in a murine model of experimental colitis and human Caco-2 cells via inhibiting NRF2/HO-1 pathway.