Protective effects of luteolin against amyloid beta-induced oxidative stress and mitochondrial impairments through peroxisome proliferator-activated receptor γ-dependent mechanism in Alzheimer's disease

Nanocarrier-mediated siRNA delivery: a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

Traumatic brain injury and Alzheimer's disease share pathological similarities, including neuronal loss, amyloid-β deposition, tau hyperphosphorylation, blood-brain barrier dysfunction, neuroinflammation, and cognitive deficits. Furthermore, traumatic brain injury can exacerbate Alzheimer's disease-like pathologies, potentially leading to the development of Alzheimer's disease. Nanocarriers offer a potential solution by facilitating the delivery of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease. Unlike traditional approaches to neuroregeneration, this is a molecular-targeted strategy, thus avoiding non-specific drug actions. This review focuses on the use of nanocarrier systems for the efficient and precise delivery of siRNAs, discussing the advantages, challenges, and future directions. In principle, siRNAs have the potential to target all genes and non-targetable proteins, holding significant promise for treating various diseases. Among the various therapeutic approaches currently available for neurological diseases, siRNA gene silencing can precisely "turn off" the expression of any gene at the genetic level, thus radically inhibiting disease progression; however, a significant challenge lies in delivering siRNAs across the blood-brain barrier. Nanoparticles have received increasing attention as an innovative drug delivery tool for the treatment of brain diseases. They are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier, targeted drug delivery, enhanced drug stability, and multifunctional therapy. The use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective approach. Although this strategy is still in the preclinical exploration stage, it is expected to achieve clinical translation in the future, creating a new field of molecular targeted therapy and precision medicine for the treatment of Alzheimer's disease associated with traumatic brain injury.

Schisandrin B ameliorates Alzheimer's disease by suppressing neuronal ferroptosis and ensuing microglia M1 polarization

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by neuronal damage, with poor prognosis and limited therapeutic options. Inhibition of neuronal ferroptosis has shown promise as a potential treatment for AD. Schisandrin B (Sch B), a major active component of Schisandra chinensis, exhibits potential neuroprotective effects. However, whether Sch B inhibits neuronal ferroptosis remains unclear.

PURPOSE

To investigate the mechanisms underlying the effects of Sch B on the GSK3β/Nrf2/GPX4 and FSP1 signaling pathways, which are the suppression of neuronal ferroptosis and the potential therapeutic intervention in AD.

METHODS

We employed the 3 × Tg mouse model in vivo, and utilized the erastin-induced ferroptosis model in SH-SY5Y/APP695swe cells in vitro. Nissl staining was conducted to facilitate histopathological assessment. Assessment of neuronal ferroptosis was performed utilizing a lipid peroxidation and ferroptosis marker assay kit. Furthermore, bioinformatic analysis was executed with the application of the GEO database. Immunofluorescence and Western blot analyses were performed to quantify protein expression levels within the cellular context. ELISA was utilized to determine cytokine concentrations within the supernatant of cell cultures. RT-PCR was executed to evaluate mRNA expression levels.

RESULTS

Sch B suppresses the activation of GSK3β, modulating the Nrf2/GPX4 signaling pathway and consequently inhibiting ferroptosis in neurons, which results in amelioration of cognitive impairment and pathological damage in 3 × Tg mice. Sch B also inhibits GSK3β activation, thereby modulating the Nrf2/GPX4 signaling pathway to prevent erastin-induced ferroptosis in SH-SY5Y695swe cells in vitro. Furthermore, Sch B modulates FSP1, enhancing its synergistic interaction with the GSK3β/Nrf2/GPX4 pathway to suppress neuronal ferroptosis. Sch B can also inhibit TNF-α release from neurons undergoing ferroptosis, thus impeding the activation of M1-type microglia, suggesting a multifaceted neuroprotective strategy against neuroinflammatory processes.

CONCLUSION

Sch B modulates the GSK3β/Nrf2/GPX4 pathway in conjunction with FSP1 to inhibit neuronal ferroptosis and the subsequent microglial M1 polarization mediated by neuronal ferroptosis, thereby improving cognitive impairment and pathological damage in AD.

Regulating environmental arsenic-mediated gut-brain toxicity using chitosan-conjugated luteolin gold nanoparticles

Anxiety and depression are two major contributors to global disease burden. Amongst various causal factors, exposure to even low doses of environmental heavy metals, like arsenic, can induce anxiety and depression-like behaviour in mammals. Ingestion of arsenic, primarily through contaminated drinking water, severely disrupts the gut microbes, thereby inducing structural and functional abnormalities in the brain. Fecal microbiota transplantation (FMT) from arsenic-exposed mice to recipient healthy mice (As-FMT) enriched LPS-secreting Gram-negative bacteria and upregulated the expression of TLR4 in intestinal epithelial cells. Consequently, inflammation, oxidative stress and compromised barrier integrity in the gut facilitated LPS translocation into the bloodstream and promoted systemic inflammation. The secretomes eventually affected the brain by activating microglia, altering neurotransmitter levels and reducing the glucocorticoid receptor (GR) expression, contributing to appearance of pyknotic nuclei in dentate gyrus of hippocampus and emergence of anxiety- and depression-like behaviour. Luteolin, a flavonoid, devoid of any apparent side-effects, yet known for its anti-inflammatory and antioxidant properties, showed potential in alleviating the gut-brain toxic effects. However, its limited solubility and bioavailability pose challenges for its effectiveness, for which chitosan-conjugated luteolin gold nanoparticles (CH-LuAuNPs) were synthesized. Interestingly, where FMT from arsenic-treated mice to healthy mice showed deleterious effects in the transplanted mice, FMT from arsenic-treated mice co-administered with CH-LuAuNP attenuated As-FMT-mediated disruption of the gut-brain axis. This study highlighted the critical contribution of healthy gut microbiota in preserving neurobehavioural physiology, as well as underscored the potential therapeutic benefits of luteolin nanoparticles in ameliorating arsenic-induced gut dysbiosis and consequent mental disorders.

Pre-clinical evidence for mitochondria as a therapeutic target for luteolin: A mechanistic view

Pre-clinical evidence indicates that mitochondria may be a therapeutic target for luteolin (3',4',5,7-tetrahydroxyflavone; LUT) in different conditions. LUT modulates mitochondrial physiology in in vitro, ex vivo, and in vivo experimental models. This flavone exerted mitochondria-related antioxidant and anti-apoptotic effects, stimulated mitochondrial fusion and fission, induced mitophagy, and promoted mitochondrial biogenesis in human and animal cells and tissues. Moreover, LUT modulated the activity of components of the oxidative phosphorylation (OXPHOS) system, improving the ability of mitochondria to produce adenosine triphosphate (ATP) in certain circumstances. The mechanism of action by which LUT promoted mitochondrial benefits and protection are not completely clear yet. Nonetheless, LUT is a potential candidate to be utilized in mitochondrial therapy in the future. In this work, it is explored the mechanisms of action by which LUT modulates mitochondrial physiology in different pre-clinical experimental models.

Application of Natural Products in Neurodegenerative Diseases by Intranasal Administration: A Review

Natural products derived from traditional Chinese medicine have received significant attention as potential treatments for neurodegenerative disorders due to their wide availability, demonstrated efficacy, and favorable safety profiles. Intranasal delivery provides distinct advantages for targeting the central nervous system (CNS), enabling direct therapeutic agent delivery to the brain by bypassing the blood-brain barrier (BBB). This review evaluates natural products administered intranasally for neurodegenerative diseases (NDs), highlighting their therapeutic potential and addressing formulation challenges related to physicochemical properties. Strategic optimization approaches are proposed, including novel carrier systems, molecular modifications, and combination therapies. By discussing current difficulties and offering practical recommendations, this review aims to encourage further scholarly research and clinical application.

Lycii Fructus and Chrysanthemum Flos, a Chinese medicine herbal pair, ameliorates retinal degeneration of mice induced by sodium iodate and protects Müller cells from oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

The combination of Lycii Fructus (LF) and Chrysanthemum Flos (CF) is a well-known herbal pair utilized in Chinese medicine for the treatment of retinal degeneration diseases commonly found in the elderly, such as age-related macular degeneration (AMD). However, the precise mechanisms of action mechanism and active constituents responsible for the therapeutic effects of the LF-CF herbal pair in improving AMD remain unknown.

AIM OF THE STUDY

This study aims to evaluate the effect of the LF-CF herbal pair on alleviating retinal damage and apoptosis in Müller cells of a dry AMD mouse model, especially its role in enhancing oxidative stress in the retina. Moreover, it endeavors to clarify the underlying action mechanisms and identify the bioactive ingredients in the LF - CF herbal pair that act on Müller cells to alleviate oxidative stress.

MATERIALS AND METHODS

A mice model of dry AMD was established through intraperitoneal administration of sodium iodate. Various solvents were employed to prepare extracts of the LF-CF herbal pair. The impact of these solvent extracts on ameliorating oxidative damage and determination of oxidation index in the retina was assessed. The ability of LF-CF herbal pair on regulating Nrf2/HO-1 signaling pathway in model mice was also detected. The MIO-M1 cell cultures were employed to assess the impact of extracts on protecting cells from oxidative damage caused by sodium iodate. The cell cultures were also utilized to investigate the potential mechanism of action and identify the active components involved.

RESULTS

The LF-CF herbal pair extracts showed evident protective effects on the mouse retina against sodium iodate-induced oxidative damage. They maintained retinal structural integrity and inhibited apoptosis. Among the extracts, the aqueous and 70 % ethanol ones were more effective in preventing retina injury. These two extracts enhanced antioxidant enzyme activity, reduced oxidative products in the experimental mice's retina, reversing the down-regulation of glutamine synthetase (a Müller cell marker). In vitro, the aqueous and 70 % ethanol extracts of the LF-CF herbal pair also protected MIO-M1 cells from sodium iodate-induced oxidative stress via regulating caspase-dependent and Nrf2/HO-1 signaling pathways. Lycium barbarum polysaccharides and luteolin are likely the active ingredients responsible for these effects.

CONCLUSIONS

The LF-CF herbal pair demonstrated the ability to mitigate oxidative stress in the retina and suppress apoptosis in Müller cells through the regulation of caspase-dependent and Nrf2/HO-1 signaling pathways. These findings contribute to the growing body of scientific evidences supporting the potential of LF-CF herbal pair as a viable therapeutic option or preventive measure for dry AMD.

A Novel Hybrid Peptide VLP-Aβ Exhibits Antioxidant Activity In Vitro and In Vivo via KEAP1-NRF2-ARE Signaling Pathway

Oxidative stress plays a crucial role in the development and progression of various diseases. Antioxidant peptides have attracted great attention in agricultural, food, and clinical fields due to their low toxicity, high efficacy, and easy absorption, but the development of antioxidant peptides and their in-depth molecular mechanisms are still lacking. The previous study established a platform for the high-throughput design and screening of multifunctional peptides and successfully identified a novel hybrid peptide, VLP-Aβ (VA), which exhibits both antioxidant and immunomodulatory properties. This study aimed to evaluate the antioxidant activity of VA and investigate the underlying molecular mechanisms. The antioxidant effects of VA were evaluated using both in vitro (H2O2-induced oxidative damage in HepG2 cells) and in vivo (CCl4-induced liver damage in mice) models. VA exhibited significant antioxidant activity both in vitro and in vivo, significantly improving the cell viability and increasing the levels of antioxidant enzymes (SOD, CAT, GSH-Px) to alleviate oxidative stress. These findings indicated that the antioxidant effect of VA is dependent on NRF2, as evidenced by NRF2 knockdown experiments. Further investigation revealed that VA alleviates oxidative stress by modulating the KEAP1-NRF2-ARE signaling pathway. These findings provide insights into the properties of the antioxidant peptide VA, expand the understanding of its molecular mechanisms, and suggest new opportunities for developing VA as a novel functional agent in the agricultural, food, and clinical industries.

The Role of Selected Flavonoids in Modulating Neuroinflammation in Alzheimer's Disease: Mechanisms and Therapeutic Potential

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, amyloid-β (Aβ) deposition, tau hyperphosphorylation, oxidative stress, and chronic neuroinflammation. Growing evidence highlights neuroinflammation-driven by microglial activation and pro-inflammatory cytokine release-as a key contributor to AD pathogenesis and progression. In the absence of effective disease-modifying therapies, attention has turned to natural compounds with multi-target potential. Flavonoids, a diverse class of plant-derived polyphenols, have demonstrated neuroprotective properties through antioxidant activity, modulation of neuroinflammatory pathways, and interference with both Aβ aggregation and tau pathology. This narrative review provides an integrative overview of current findings on the mechanisms of action of key flavonoids-such as quercetin, luteolin, and apigenin-in both preclinical and clinical models. Emphasis is placed on their effects on microglial polarization, oxidative stress reduction, mitochondrial support, and synaptic function enhancement. Moreover, flavonoids show synergistic potential when combined with standard pharmacotherapies, such as acetylcholinesterase inhibitors, and may offer broader cognitive benefits in patients with mild cognitive impairment (MCI). Despite these promising findings, significant challenges persist, including poor bioavailability, inter-individual variability, and limited long-term clinical data. This review identifies critical gaps in knowledge and outlines future directions, including targeted drug delivery systems, biomarker-guided personalization, and long-duration trials. Flavonoids thus emerge not only as promising neuroprotective agents but also as complementary candidates in the development of future multi-modal strategies for AD treatment.

Functionalized carbon dots with guanidine salt ionic liquid regulate oxidative damage and amyloid aggregation

An imbalance in the brain microenvironment, involving oxidative stress and β-amyloid (Aβ) accumulation, is thought to be one of the primary characteristics of early Alzheimer's disease (AD). To address the intricate pathophysiology of AD, therapeutic approaches that can concurrently control several diseases in the AD microenvironment are desperately needed. This study created a guanidine salt ionic liquid functionalized carbon dots (CDs@TGM-IL) to mitigate Aβ aggregation-induced cytotoxicity and scavenge reactive oxygen species (ROS) simultaneously. In vitro studies have shown that CDs@TGM-IL can effectively inhibit Aβ42 protein aggregation, disaggregate mature Aβ42 fibrils, and effectively remove ROS. In vivo studies have found that CDs@TGM-IL can cross the blood-brain barrier (BBB) and improve cognitive performance in AD mice. Just as importantly, CDs@TGM-IL has been shown to have unparalleled biocompatibility. This means that CDs@TGM-IL is expected to be a possible treatment for AD.

The role of semaphorin 3A in the pathogenesis and progression of Alzheimer's disease and other aging-related diseases: A comprehensive review

Aging serves as a pivotal factor in the etiology of numerous diseases, such as Alzheimer's disease (AD), Parkinson's disease, diabetes, osteoarthritis, atherosclerosis and aging-related macular degeneration. Notably, these diseases often interact with AD through various pathways, facilitating the onset or progression of one another. Semaphorin 3 A (Sema3A), a protein that is essential for axonal guidance during neural development, has recently been identified as a novel regulator in the pathogenesis and progression of multiple aging-related diseases. This article provides a comprehensive review of the expression patterns and mechanisms of action of Sema3A in these diseases. Specifically, Sema3A influences the occurrence and development of aging-related diseases by participating in oxidative stress, inflammatory responses, apoptosis, and synaptic plasticity. Therefore, therapeutic strategies targeting Sema3A present promising avenues for delaying the progression of aging-related diseases and offer novel insights and strategies for their treatment.

Luteolin attenuates cadmium neurotoxicity by suppressing glial inflammation and supporting neuronal survival

Cadmium (Cd), a neurotoxic metal, is associated with the development of neurological disorders. This study investigated the neuroprotective effects of Luteolin against Cd-induced toxicity in cultured cells and mouse models. Our findings demonstrate that Luteolin protects hippocampal neurons from Cd toxicity and mitigates Cd-triggered inflammatory responses in microglial BV2 cells. In Cd-exposed mice, symptoms such as weight loss, motor retardation, multi-organ damage, and cognitive deficits were observed. Remarkably, Luteolin treatment reversed these effects, repaired organ damage, and restored learning and memory abilities. Mechanistically, Cd toxicity induced significant upregulation of pro-inflammatory factors and neuroinflammation in the hippocampus and prefrontal cortex, including elevated glial cell markers (IBA1, GFAP, and CD68) and reduced neuronal marker MAP2. Luteolin counteracted these adverse effects by inhibiting the Notch1/Hes1 inflammatory signaling axis and restoring the BDNF-TrkB/AKT1 signaling axis, thereby promoting neuronal survival. These results highlight the potential of Luteolin as a natural neuroprotective agent against Cd-induced neurotoxicity, offering a promising therapeutic strategy for mitigating Cd-related neurological damage.

The antidepressant effects of kaji-ichigoside F1 via activating PPAR-γ/CX3CR1/Nrf2 signaling and suppressing NF-κB/NLRP3 signaling pathways

Introduction

Depression is a mental illness closely associated with neurological damage and is characterised by high rates of suicide and mood changes. As a traditional medicinal plant, Rosa roxburghii Tratt has been widely used since ancient times in the Miao and Dong regions of Southwest China for the relief of sleep disorders, indigestion, anti-inflammation, neurasthenia and neuroprotection. The total triterpenes of R. roxburghii were previously found to have certain neuroprotective effects, and whether Kaji-ichigoside F1 (KF1), as its main ingredient, plays a relevant pharmacological role needs to be further investigated.

Methods

Establishment of mouse depression model and BV2 microglia inflammation model using intraperitoneal injection of LPS in mice and LPS stimulated-BV2 microglia, respectively. The antidepressant effects of KF1 were evaluated by forced swim test (FST), sucrose preference test (SPT), tail suspension test (TST) and open field test (OFT). The number of Nissl bodies and apoptotic positive cells in the CA1 region of the hippocampus was observed by Nissl and TUNEL staining. Then, the levels of TNFα, PPAR-γ, TGF-β, and IL-6 cytokines were tested by ELISA kits. Finally, the molecular mechanisms were investigated by Western blotting (WB) and immunofluorescence in vivo and in vitro.

Results

KF1 dramatically ameliorated LPS-induced depressive like behaviors, neuronal damage, apoptosis, and suppressed the levels of pro-inflammatory cytokines in the serum and hippocampus of mice. Our vitro experiment also showed KF1 significantly reduced cell viability and attenuated apoptosis in LPS-induced BV2 microglia, decreased the mean fluorescence intensity of Caspase-1, TNFα, NF-κB, IL-1β, NLRP3, and Keap1. However, the mean fluorescence intensity of GCLC, GCLM, GST, SOD1, HO-1, and Nrf2 were significantly increased. Finally, Western blot analysis showed that KF1 suppressing the expression of NF-κB/NLRP3 signaling pathway and activating PPARγ/CX3CR1/Nrf2 signaling pathway both in vivo and in vitro.

Conclusion

In conclusion, these results suggest that KF1 is an effective alleviator of LPS-induced depression-like effects in vivo and in vitro. These effects were associated with activating PPARγ/CX3CR1/Nrf2 signaling, and suppressing NF-κB/NLRP3 signaling pathways.

Regulation of Apoptotic Pathways by MicroRNAs: A Therapeutic Strategy for Alzheimer's Disease

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder marked by a gradual decline in memory and cognitive functions. It is characterized by the presence of senile plaques, neurofibrillary tangles, and neuronal degeneration, affecting a significant portion of the human population. A key feature of various nervous system disorders, including AD, is extensive cellular death caused by apoptosis, which affects not only neurons but also glial cells. While apoptosis plays a vital role in eliminating certain cells and supporting normal development, alterations or disruptions in apoptotic pathways can lead to harmful neurodegenerative conditions such as AD. Thus, targeting apoptosis presents a promising therapeutic approach for these diseases. MicroRNAs (miRNAs), a class of non-coding RNA, play diverse roles in cellular functions, including proliferation, gene expression regulation, programmed cell death, intercellular communication, and angiogenesis. By modulating regulatory genes, miRNAs can influence apoptosis, either promoting or inhibiting it. Aberrant expression of miRNAs can impact multiple apoptotic pathways, potentially driving the progression of AD and related health issues. This review summarizes recent research on miRNAs and their dual role in exacerbating or protecting against neural cell damage in AD by altering apoptotic pathways. The regulation of apoptosis by miRNAs offers a prospective therapeutic strategy for Alzheimer's disease.

Neochlorogenic acid ameliorates Alzheimer's disease-like pathology via scavenging oxidative stress and restoring blood-brain barrier function in zebrafish

Alzheimer's disease is the most widespread neurodegenerative disease characterized by insidious onset and slow progression. At present, most available medications serve to attenuate the progression of Alzheimer's disease with side effects and drug resistance. Neochlorogenic acid is a natural polyphenolic compound with excellent antioxidant properties. Based on zebrafish Alzheimer's disease model induced by AlCl3, we found that neochlorogenic acid significantly improved motor dysfunction, reduced brain cell apoptosis, and Aβ plaque. Because of antioxidant stress and improvement of blood-brain barrier dysfunction are important in treating Alzheimer's disease, we explored the interaction between these two mechanisms in alleviating the pathological course of Alzheimer's disease. Neochlorogenic acid inhibited the overproduction of reactive oxygen species, suppressed the gene expression encoding antioxidant-related proteins, and protected brain cell integrity while enhancing Nrf2, improving blood-brain barrier nerve resilience. Meanwhile, neochlorogenic acid attenuated blood-brain barrier dysfunction in Alzheimer's disease zebrafish by reducing blood hemoglobin leakage and upregulating the gene expression encoding blood-brain barrier endothelial cell-related proteins, resulting in reactive oxygen species in a controllable state. In conclusion, our research suggests that neochlorogenic acid ameliorates Alzheimer's disease-like pathology by inhibiting oxidative stress and restoring blood-brain barrier function, indicating that neochlorogenic acid may be a potential drug for treating Alzheimer's disease.

Investigation into Alzheimer's-related amyloid-β conformational transformations and stability influenced by green iron oxide nanoparticles (GIONP)

Alzheimer's disease (AD) is popularly believed to be triggered by the aggregation of amyloid beta 1-42 (Aβ - 42) peptides, eventually leading to neurodegeneration. Our study delves into the influential role played by Green Iron Oxide Nanoparticles (GIONP). GIONP are typically synthesized using a green chemistry approach, imposing curcumin as a biocompatible reducing and capping agent, leveraging its inherent antioxidant, anti-inflammatory, and neuroprotective attributes. Herein, our research particularly aims to decipher whether GIONP modulates the secondary structure of Aβ1-42 peptides with a close consideration to the surrounding physiological factors, as well as the membrane bilayer probable conformation changes. Raman spectroscopy was employed to investigate the interaction between GIONP and Aβ1-42 aggregates, demonstrating significant alterations in secondary structure dynamics of Aβ1-42 polypeptide. Fourier-transform infrared (FTIR) spectroscopy shed light on the chemical interactions between GIONP and curcumin, a capping agent. X-ray diffraction (XRD) analysis was performed to determine the crystalline structure and phase purity of the synthesized GIONP, providing insights into their stability and structural integrity. GIONP particle size distribution investigations and membrane architectures surrounding GIONP were carried out for their impact on membrane integrity and stability. The morphology of GIONP, membrane mimetic liposomal structures formation, and integrity were studied using transmission electron microscopy (TEM), accompanied with energy-dispersive X-ray spectroscopy (EDS), which displayed the elements distribution within each of the structures. The study uncovered that GIONP stabilizes the secondary structure of Aβ1-42, potentially offering modulation to the aggregation process. Furthermore, GIONP proved to have no negative impact on membrane integrity, implying that they could be safely employed as a therapeutic option for the modulation of peptide aggregation's pathological pathway of Alzheimer's disease. This study may contribute to broadening our understanding of nanoparticle-mediated therapies in modulating neurodegenerative disorders, highlighting their dual involvement in amyloid aggregation regulation and membrane structure maintenance.

Sclareol improves the pathology of Alzheimer's disease by inhibiting microglial inflammation via interacting with CDK9

BACKGROUND

Excessive activation of microglia triggers pro-inflammatory responses, exacerbating neuronal damage and accelerating the progression of Alzheimer's disease (AD). Thus, targeting abnormal microglial activation represents a promising therapeutic strategy for AD. In this study, we identified sclareol (SCL) through compound library screening as a potent anti-inflammatory agent capable of crossing the blood-brain barrier. However, there are currently no reports on whether SCL modulates microglial inflammation or ameliorates AD pathology.

OBJECTIVE

To evaluate the anti-inflammatory effects and underlying molecular mechanism of SCL on microglial-mediated inflammation and neuronal damage in AD.

METHODS

Drug Affinity Responsive Target Stability (DARTS), Liquid Chromatography-Tandem Mass Spectrometry (LC-MS), protein interaction assays, Biolayer Interferometry (BLI), and molecular docking were used to explore the interaction between SCL and cyclin-dependent kinase 9 (CDK9). Behavioral tests and immunofluorescent (IF) staining were performed to assess the effects of SCL on microglial activation and AD pathology. The molecular mechanism of the anti-inflammatory effect of SCL was analyzed by interfering with CDK9.

RESULTS

SCL significantly inhibited the release of proinflammatory mediators, reduced neuronal damage, and alleviated cognitive deficits in AD model mice. Notably, SCL demonstrated the ability to cross the blood-brain barrier (BBB), highlighting its therapeutic potential. Mechanistically, SCL binds directly to CDK9, which contributes to the inflammatory response through its interaction with NF-κB. Knockdown of CDK9 reduced the NF-κB-mediated inflammatory response, but did not have an additive effect on SCL, indicating that SCL's efficacy is mediated by CDK9 inhibition and subsequent suppression of the NF-κB signaling pathway.

CONCLUSION

This study demonstrates that SCL exerts neuroprotective effects in AD mice by targeting CDK9 and downstream NF-κB signaling pathway to reduce the inflammatory activation of microglia. These findings suggest that SCL is a promising candidate for the treatment of AD, offering a novel therapeutic approach to mitigate disease progression through modulation of microglial activation.

Lycium ruthenicum Murray exosome-like nanovesicles alleviated Alzheimer's disease-like symptoms induced by Aβ protein in transgenic Caenorhabditis elegans through the DAF-16 pathway

Alzheimer's disease (AD) is predominantly characterized by cholinergic dysfunction, mitochondrial impairment, oxidative stress, and inflammation, primarily driven by amyloid-beta (Aβ) peptides. This study investigates the protective effects of Lycium ruthenicum Murray-derived exosome-like nanoparticles (LELN) in AD models using transgenic Caenorhabditis elegans (C. elegans). Findings showed that C. elegans effectively internalized LELN, which remained stable in vivo. Compared with untreated controls, treatment with 600 μg/mL LELN significantly extended the lifespan of CL4176 [myo-3p::Aβ1-42] and CL2006 [unc-54/Aβ1-42] worms by 34.78 % and 34.85 %, respectively, and delayed Aβ-induced paralysis by 52.42 % and 42.72 %, respectively. Furthermore, LELN increased the chemotaxis index of CL2355 [snb-1::Aβ1-42] worms from 11.11 % to 55.56 %. Mechanistically, LELN reduced the levels of Aβ oligomers and monomers via the DAF-16 pathway, consequently alleviating AD-like symptoms in transgenic C. elegans. The effects of LELN include inhibiting acetylcholinesterase activity to mitigate cholinergic dysfunction, restoring mitochondrial membrane potential and adenosine triphosphate production to ameliorate mitochondrial dysfunction, and reducing oxidative stress and inflammation. Collectively, these results highlight the protective role of LELN against Aβ-induced AD pathology and underscore their potential as a therapeutic candidate for AD treatment.

Mitochondrial quality control disorder in neurodegenerative disorders: Potential and advantages of traditional Chinese medicines

Neurodegenerative disorders (NDDs) are prevalent chronic conditions characterized by progressive synaptic loss and pathological protein alterations. Increasing evidence suggested that mitochondrial quality control (MQC) serves as the key cellular process responsible for clearing misfolded proteins and impaired mitochondria. Herein, we provided a comprehensive analysis of the mechanisms through which MQC mediates the onset and progression of NDDs, emphasizing mitochondrial dynamic stability, the clearance of damaged mitochondria, and the generation of new mitochondria. In addition, traditional Chinese medicines (TCMs) and their active monomers targeting MQC in NDD treatment have been demonstrated. Consequently, we compiled the TCMs that show great potential in the treatment of NDDs by targeting MQC, aiming to offer novel insights and a scientific foundation for the use of MQC stabilizers in NDD prevention and treatment.

Synaptic plasticity and neuroprotection: The molecular impact of flavonoids on neurodegenerative disease progression

Flavonoids are a broad family of polyphenolic chemicals that are present in a wide variety of fruits, vegetables, and medicinal plants. Because of their neuroprotective qualities, flavonoids have attracted a lot of interest. The potential of flavonoids to control synaptic plasticity-a crucial process underlying memory, learning, and cognitive function-is becoming more and more clear. Dysregulation of synaptic plasticity is a feature of neurodegenerative diseases such as amyotrophic lateral sclerosis (0.4 %), Parkinson's (1-2 %), Alzheimer's (5-7 %), and Huntington's ((0.2 %)). This review discusses the molecular mechanisms via which flavonoids influence synaptic plasticity as well as their therapeutic potential in neurodegenerative diseases. Flavonoids modulate key signaling pathways such as MAPK/ERK and PI3K/Akt/mTOR to support neuroprotection, synaptic plasticity, and neuronal health, while also influencing neurotrophic factors (BDNF, NGF) and their receptors (TrkB, TrkA). They regulate neurotransmitter receptors like GABA, AMPA, and NMDA to balance excitatory and inhibitory transmission, and exert antioxidant effects via the Nrf2-ARE pathway and anti-inflammatory actions by inhibiting NF-κB signaling, highlighting their potential for treating neurodegenerative diseases. These varied reactions support the preservation of synapse function and neuronal integrity in the face of neurodegenerative insults. Flavonoids can reduce the symptoms of neurodegeneration, prevent synaptic loss, and enhance cognitive function, according to experimental studies. However, there are still obstacles to using these findings in clinical settings, such as limited bioavailability and the need for consistent dose. The focus of future research should be on improving flavonoid delivery systems and combining them with conventional medications.

Luteolin ameliorates chronic stress-induced depressive-like behaviors in mice by promoting the Arginase-1+ microglial phenotype via a PPARγ-dependent mechanism

Accumulating evidence shows that neuroinflammation substantially contributes to the pathology of depression, a severe psychiatric disease with an increasing prevalence worldwide. Although modulating microglial phenotypes is recognized as a promising therapeutic strategy, effective treatments are still lacking. Previous studies have shown that luteolin (LUT) has anti-inflammatory effects and confers benefits on chronic stress-induced depression. In this study, we investigated the molecular mechanisms by which LUT regulates the functional phenotypes of microglia in mice with depressive-like behaviors. Mice were exposed to chronic restraint stress (CRS) for 7 weeks, and were administered LUT (10, 30, 40 mg· kg-1 ·day-1, i.g.) in the last 4 weeks. We showed that LUT administration significantly ameliorated depressive-like behaviors and decreased hippocampal inflammation. LUT administration induced pro-inflammatory microglia to undergo anti-inflammatory arginase (Arg)-1+ phenotypic polarization, which was associated with its antidepressant effects. Furthermore, we showed that LUT concentration-dependently increased the expression of PPARγ in LPS + ATP-treated microglia and the hippocampus of CRS-exposed mice, promoting the subsequent inhibition of the NLRP3 inflammasome. Molecular dynamics (MD) simulation and microscale thermophoresis (MST) analysis confirmed a direct interaction between LUT and peroxisome proliferator-activated receptor gamma (PPARγ). By using the PPARγ antagonist GW9662, we demonstrated that LUT-driven protection, both in vivo and in vitro, resulted from targeting PPARγ. First, LUT-induced Arg-1+ microglia were no longer detected when PPARγ was blocked. Next, LUT-mediated inhibition of the NLRP3 inflammasome and downregulation of pro-inflammatory cytokine production were reversed by the inhibition of PPARγ. Finally, the protective effects of LUT, which attenuated the microglial engulfment of synapses and prevented apparent synapse loss in the hippocampus of CRS-exposed mice, were eliminated by blocking PPARγ. In conclusion, this study showed that LUT ameliorates CRS-induced depressive-like behaviors by promoting the Arg-1+ microglial phenotype through a PPARγ-dependent mechanism, thereby alleviating microglial pro-inflammatory responses and reversing microglial phagocytosis-mediated synapse loss.

Effect of Luteolin Nanoparticles on Bond Strength, Hardness, and Roughness of Tissue Conditioners: An In Vitro Study

Background

Tissue conditioners are widely used to manage traumatized oral tissues under dentures, but their mechanical limitations restrict long-term use. Luteolin, a flavonoid with known anti-inflammatory and wound healing properties, may enhance these materials when incorporated as nanoparticles (NPs).

Aim

To investigate the effect of incorporating luteolin NPs into an acrylic-based tissue conditioner on its tensile bond strength, surface hardness, and surface roughness.

Materials and Methods

Sixty samples were divided into control (n = 15) and experimental groups (n = 45), with luteolin NPs incorporated at 1%, 2%, and 4% w/w concentrations. Tensile bond strength was tested using a universal testing machine, surface hardness via Shore A durometer, and surface roughness with a profilometer. Data were analyzed using analysis of variance and Tukey's post hoc test (P ≤ 0.05).

Results

The 2% luteolin NP group demonstrated the highest tensile bond strength (0.28 MPa), lowest surface hardness (26.52), and surface roughness (2.20 µm). Incorporation at 2% and 4% significantly improved bond strength, while 1% and 2% significantly reduced surface hardness (P < 0.05). No statistically significant change in surface roughness was observed across groups.

Conclusion

Tissue conditioners modified with 2% luteolin NPs showed improved bonding and optimal surface properties without compromising material performance. These findings support the potential clinical utility of luteolin-enhanced tissue conditioners for managing traumatized oral tissues.

Polyphenols, Alkaloids, and Terpenoids Against Neurodegeneration: Evaluating the Neuroprotective Effects of Phytocompounds Through a Comprehensive Review of the Current Evidence

Neurodegenerative diseases comprise a group of chronic, usually age-related, disorders characterized by progressive neuronal loss, deformation of neuronal structure, or loss of neuronal function, leading to a substantially reduced quality of life. They remain a significant focus of scientific and clinical interest due to their increasing medical and social importance. Most neurodegenerative diseases present intracellular protein aggregation or their extracellular deposition (plaques), such as α-synuclein in Parkinson's disease and amyloid beta (Aβ)/tau aggregates in Alzheimer's. Conventional treatments for neurodegenerative conditions incur high costs and are related to the development of several adverse effects. In addition, many patients are irresponsive to them. For these reasons, there is a growing tendency to find new therapeutic approaches to help patients. This review intends to investigate some phytocompounds' effects on neurodegenerative diseases. These conditions are generally related to increased oxidative stress and inflammation, so phytocompounds can help prevent or treat neurodegenerative diseases. To achieve our aim to provide a critical assessment of the current literature about phytochemicals targeting neurodegeneration, we reviewed reputable databases, including PubMed, EMBASE, and COCHRANE, seeking clinical trials that utilized phytochemicals against neurodegenerative conditions. A few clinical trials investigated the effects of phytocompounds in humans, and after screening, 13 clinical trials were ultimately included following PRISMA guidelines. These compounds include polyphenols (flavonoids such as luteolin and quercetin, phenolic acids such as rosmarinic acid, ferulic acid, and caffeic acid, and other polyphenols like resveratrol), alkaloids (such as berberine, huperzine A, and caffeine), and terpenoids (such as ginkgolides and limonene). The gathered evidence underscores that quercetin, caffeine, ginkgolides, and other phytochemicals are primarily anti-inflammatory, antioxidant, and neuroprotective, counteracting neuroinflammation, neuronal oxidation, and synaptic dysfunctions, which are crucial aspects of neurodegenerative disease intervention in various included conditions, such as Alzheimer's and other dementias, depression, and neuropsychiatric disorders. In summary, they show that the use of these compounds is related to significant improvements in cognition, memory, disinhibition, irritability/lability, aberrant behavior, hallucinations, and mood disorders.

Unlocking the Therapeutic Potential of Natural Products for Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative condition marked by memory loss and cognitive decline. With current treatments offering limited effectiveness, researchers are turning to natural products that can target various aspects of AD pathology. Clinically approved natural products, such as galantamine and huperzine A, have shown success in AD treatments. Furthermore, compounds such as epigallocatechin gallate, quercetin, and resveratrol are in clinical trials. This Perspective examines nearly 100 natural compounds with promising neuroprotective effects in preclinical and clinical studies. These compounds exhibit diverse pharmacological actions that help to prevent neurodegeneration while improving cognitive functions. Their unique structures further enhance their biological activities, making them promising candidates for drug discovery. This Perspective stresses the importance of further clinical research to maximize the medical benefits of these compounds and highlights their potential as innovative remedies for AD. Continued exploration of these compounds is crucial to fully leverage their capabilities in combating AD.

TMF Attenuates Cognitive Impairment and Neuroinflammation by Inhibiting the MAPK/NF-κB Pathway in Alzheimer's Disease: A Multi-Omics Analysis

The rising prevalence of Alzheimer's disease (AD) underscores the urgent need for novel therapeutic agents derived from natural sources. Among flavonoids, 3',4',5,7-tetramethoxyflavone (TMF), a structural analog of luteolin, has gained attention for its favorable pharmacokinetics and potential neuroprotective properties. Despite the significant neuroprotective effects and favorable pharmacokinetics of TMF, its efficacy and mechanism of action in AD remain unclear. This study explored TMF's pharmacological effects in AD models, highlighting its ability to improve memory and cognitive deficits in APP/PS1 mice. TMF reduced Aβ plaques, NFTs formation, and glial activation while suppressing neuroinflammation through the MAPK/NF-κB pathway. Further analysis in LPS-induced BV2 cells revealed TMF's ability to reduce microglial activation. These findings highlight the anti-neuroinflammatory activity of TMF, suggesting its potential as a treatment for AD.

Efficacy and molecular mechanisms of hesperidin in mitigating Alzheimer's disease: A systematic review

Hesperidin, a flavonoid glycoside, is a natural phenolic compound that has broad biological effects. Increasing evidence suggests that hesperidin inhibits the occurrence and development of neurodegenerative diseases, including Alzheimer's disease (AD). This article reviews the neuropharmacological mechanisms of hesperidin in the prevention and treatment of AD through in vitro and in vivo studies. A systematic review of preclinical studies was conducted using PubMed, Web of Science, Scopus, and Google Scholar (up to July 1, 2024). The neuroprotective potential of hesperidin was mediated through mechanisms such as inhibition of β-amyloid (Aβ) aggregation, enhancement of endogenous antioxidant defense functions, reduction of neuroinflammation and apoptosis, improvement of mitochondrial dysfunction, regulation of autophagy, and promotion of neurogenesis. Despite various preclinical studies on the role of hesperidin in AD, its exact effects on humans remain unclear. Few clinical trials have indicated that dietary supplements rich in hesperidin can improve cerebral blood flow, cognition, and memory performance. The neuroprotective effect of hesperidin may be exerted via regulating different molecular pathways, including the RAGE/NF-κB, Akt/Nrf2, and AMPK/BDNF/CREB pathways. However, further clinical trials are needed to confirm the neuroprotective effects of this natural flavonoid compound and to assess its safety.

Ganaxolone Reverses the Effect of Amyloid β-Induced Neurotoxicity by Regulating the Liver X Receptor Expression in APP Transfected SH-SY5Y Cells and Murine Model of Alzheimer's Disease

Inhibiting β-amyloid aggregation and enhancing its clearance are the key strategies in Alzheimer's disease (AD) treatment. Liver X receptors (LXRs) plays a crucial role in cholesterol homeostasis and inflammation, and their activation can clear Aβ aggregates in AD. Allopregnanolone, a neurosteroid, positively influences AD through LXR regulation, while ganaxolone, its synthetic analog, is known for its neuroprotective properties. This study explores the effect of ganaxolone on LXR activation and regulation of genes involved in mitigating Aβ toxicity and tauopathy in SH-SY5Y cells transfected with APP695 Swe/Ind plasmid and an Aβ1-42 induced AD mouse model. Molecular docking stimulations indicated ganaxolone's binding and interaction with LXRβ. Subsequently, transfected neuronal cells exhibited increased mRNA levels of APP, TNF-α and IL-1β, decreased cell viability, reduced MMP and altered protein expression of Aβ, LXR, BCL-2, APOE, ABCA1, along with increased levels of mROS, Bax, and caspase 3 activity. Ganaxolone treatment significantly abrogated Aβ-induced effect in transfected neuronal cells by enhancing LXRβ expression, inducing LXR:RXR colocalization, thereby increasing APOE and ABCA1 expression. It also decreased tau mRNA levels in transfected cells. Importantly, in AD mice, ganaxolone ameliorated cognitive impairment, reduced Aβ toxicity, tau levels, and neuroinflammatory markers, restored mitochondrial function, and decreased neuronal apoptosis. Taken together, these novel results highlight the central role of LXR in mediating Aβ-induced toxicity and provide preclinical evidence for ganaxolone as a potential agent to reduce toxicity in an LXR-dependent manner. This may serve as a promising treatment strategy to slow or prevent neurodegeneration in AD patients.

Shenghui decoction inhibits neuronal cell apoptosis to improve Alzheimer's disease through the PDE4B/cAMP/CREB signaling pathway

BACKGROUND

Shenghui Decoction (SHD) is a frequently utilized traditional Chinese medicine formula in clinical settings for addressing cognitive impairment in elderly individuals. Nevertheless, the precise mechanism by which SHD exerts its effects on the most prevalent form of dementia, Alzheimer's disease (AD), remains to be elucidated.

METHODS

Temperature-induced transgenic C. elegans assess Aβ deposition and toxicity. Behavioral experiments are utilized to assess learning and memory capabilities as well as cognitive impairment in APP/PS1 mice. Immunofluorescence and immunohistochemistry are employed to identify Aβ deposits, while UHPLCOE/MS combine network pharmacology is utilized to characterize chemical composition, predict target and analyze the biological processes and signaling pathways modulated by SHD. Molecular biology methodologies confirm the functionality of regulatory pathways. Molecular docking, molecular dynamic simulations (MD) and ultrafiltration-liquid chromatography/mass spectrometry (LC/MS) are employed for the assessment of the binding interactions between active ingredients of SHD and target proteins.

RESULTS

SHD effectively reduced the deposition of Aβ in the head of C. elegans and mitigated its toxicity, as well as improved the learning deficits and cognitive impairment in APP/PS1 mice. Network pharmacology analyses revealed that G protein-coupled receptors (GPCRs) and cell apoptosis are the primary biological processes modulated by SHD, with KEEG results indicating that SHD regulated the cAMP signaling pathway. Subsequent experimental investigations demonstrated that SHD attenuated the loss of neurons in APP/PS1 mice, upregulated the expression of anti-apoptotic protein Bcl-2 and downregulated the expression of pro-apoptotic proteins like cleave-Caspase-3 both in vivo and in vitro. Additionally, SHD decreased intracellular AMP levels while increasing cAMP levels, leading to the phosphorylation of PKA to activate CREB. This process ultimately regulated the expression of Bcl-2, Bdnf, among others, to prevent cell apoptosis and safeguard neurons. Molecular docking, MD, and ultrafiltration-LC/MS revealed that the active constituents of SHD formed stable interactions with the cAMP hydrolysis enzyme phosphodiesterase 4B (PDE4B).

CONCLUSION

SHD regulated the cAMP/CREB signaling pathway to inhibit neuronal cell apoptosis and improve AD. Furthermore, it is worth noting that this mechanism may be associated with the specific and consistent binding of SHD active ingredients to PDE4B, potentially offering promising candidates for drug development aimed at addressing AD.

The role of mitochondrial remodeling in neurodegenerative diseases

Neurodegenerative diseases are a group of diseases that pose a serious threat to human health, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and Amyotrophic Lateral Sclerosis (ALS). In recent years, it has been found that mitochondrial remodeling plays an important role in the onset and progression of neurodegenerative diseases. Mitochondrial remodeling refers to the dynamic regulatory process of mitochondrial morphology, number and function, which can affect neuronal cell function and survival by regulating mechanisms such as mitochondrial fusion, division, clearance and biosynthesis. Mitochondrial dysfunction is an important intrinsic cause of the pathogenesis of neurodegenerative diseases. Mitochondrial remodeling abnormalities are involved in energy metabolism in neurodegenerative diseases. Pathological changes in mitochondrial function and morphology, as well as interactions with other organelles, can affect the energy metabolism of dopaminergic neurons and participate in the development of neurodegenerative diseases. Since the number of patients with PD and AD has been increasing year by year in recent years, it is extremely important to take effective interventions to significantly reduce the number of morbidities and to improve people's quality of life. More and more researchers have suggested that mitochondrial remodeling and related dynamics may positively affect neurodegenerative diseases in terms of neuronal and self-adaptation to the surrounding environment. Mitochondrial remodeling mainly involves its own fission and fusion, energy metabolism, changes in channels, mitophagy, and interactions with other cellular organelles. This review will provide a systematic summary of the role of mitochondrial remodeling in neurodegenerative diseases, with the aim of providing new ideas and strategies for further research on the treatment of neurodegenerative diseases.

Recent advances and therapeutic applications of PPARγ-targeted ligands based on the inhibition mechanism of Ser273 phosphorylation

PPARγ functions as a master ligand-dependent transcription factor that regulates the expressions of a variety of key genes related to metabolic homeostasis and inflammatory immunity. It has been recognized as a popular and druggable target in modern drug discovery. Similar to other nuclear receptors, PPARγ is a phosphoprotein, and its biological functions are regulated by phosphorylation, especially at Ser273 site which is mediated by CDK5 or ERK. In the past decade, the excessive level of PPARγ-Ser273 phosphorylation has been confirmed to be a crucial factor in promoting the occurrence and development of some major diseases. Ligands capable of inhibiting PPARγ-Ser273 phosphorylation have shown great potentials for treatment. Despite these achievements, to our knowledge, no related review focusing on this topic has been conducted so far. Therefore, we herein summarize the basic knowledge of PPARγ and CDK5/ERK-mediated PPARγ-Ser273 phosphorylation as well as its physiopathological role in representative diseases. We also review the developments and therapeutic applications of PPARγ-targeted ligands based on this mechanism. Finally, we suggest several directions for future investigations. We expect that this review can evoke more inspiration of scientific communities, ultimately facilitating the promotion of the PPARγ-Ser273 phosphorylation-involved mechanism as a promising breakthrough point for addressing the clinical treatment of human diseases.

Luteolin inhibits BHV-1 replication and alleviates virus-induced inflammatory responses by regulating PI3K/AKT pathway

Bovine herpesvirus type 1 (BHV-1) seriously affects the production safety of the cattle industry and leads to epidemics worldwide. Luteolin (Lut), a flavonoid substance, can be found in vegetables, fruits, and herbs and possesses various biological properties. Here, we found that Lut can dose-dependently and significantly inhibit the cytopathic effects of BHV-1, decrease the viral titer, and suppress the BHV-1 gB gene and VP8 protein levels on bovine nasal turbinate osteoblasts (BT) and bovine kidney epithelial cells (MDBK). Mechanistic studies revealed that Lut can stably bind to the active sites of PI3K and AKT, and inhibit the PI3K/AKT pathway. Interestingly, 740Y-P (an agonist of the PI3K/AKT pathway) significantly attenuated the anti-BHV-1 effects of Lut. Further studies on the anti-inflammatory effects of Lut revealed that it attenuated BHV-1-induced activation of the NFκB pathway, which significantly suppressed the expression of TNF-α, IL-1β, IL-6, and IL-8 and increased the expression levels of IL-4 and IL-10. The PI3K/AKT pathway was also found to be involved in the anti-inflammatory effects of Lut. These results confirm the inhibitory effect of Lut on BHV-1 replication, which lays the foundation for further studies on the prevention and control of BHV-1.

Recent Insights on the Role of Nuclear Receptors in Alzheimer's Disease: Mechanisms and Therapeutic Application

Nuclear receptors (NRs) are ligand-activated transcription factors that regulate a broad array of biological processes, including inflammation, lipid metabolism, cell proliferation, and apoptosis. Among the diverse family of NRs, peroxisome proliferator-activated receptors (PPARs), estrogen receptor (ER), liver X receptor (LXR), farnesoid X receptor (FXR), retinoid X receptor (RXR), and aryl hydrocarbon receptor (AhR) have garnered significant attention for their roles in neurodegenerative diseases, particularly Alzheimer's disease (AD). NRs influence the pathophysiology of AD through mechanisms such as modulation of amyloid-beta (Aβ) deposition, regulation of inflammatory pathways, and improvement of neuronal function. However, the dual role of NRs in AD progression, where some receptors may exacerbate the disease while others offer therapeutic potential, presents a critical challenge for their application in AD treatment. This review explores the functional diversity of NRs, highlighting their involvement in AD-related processes and discussing the therapeutic prospects of NR-targeting strategies. Furthermore, the key challenges, including the necessity for the precise identification of beneficial NRs, detailed structural analysis through molecular dynamics simulations, and further investigation of NR mechanisms in AD, such as tau pathology and autophagy, are also discussed. Collectively, continued research is essential to clarify the role of NRs in AD, ultimately facilitating their potential use in the diagnosis, prevention, and treatment of AD.

Current Status of Plant-Based Bioactive Compounds as Therapeutics in Alzheimer's Diseases

Alzheimer's disease (AD) is a common central neurodegenerative disease disorder characterized primarily by cognitive impairment and non-cognitive neuropsychiatric symptoms that significantly impact patients' daily lives and behavioral functioning. The pathogenesis of AD remains unclear and current Western medicines treatment are purely symptomatic, with a singular pathway, limited efficacy, and substantial toxicity and side effects. In recent years, as research into AD has deepened, there has been a gradual increase in the exploration and application of medicinal plants for the treatment of AD. Numerous studies have shown that medicinal plants and their active ingredients can potentially mitigate AD by regulating various molecular mechanisms, including the production and aggregation of pathological proteins, oxidative stress, neuroinflammation, apoptosis, mitochondrial dysfunction, neurogenesis, neurotransmission, and the brain-gut microbiota axis. In this review, we analyzed the pathogenesis of AD and comprehensively summarized recent advancements in research on medicinal plants for the treatment of AD, along with their underlying mechanisms and clinical evidence. Ultimately, we aimed to provide a reference for further investigation into the specific mechanisms through which medicinal plants prevent and treat AD, as well as for the identification of efficacious active ingredients derived from medicinal plants.

Integrating network pharmacology and multi-omics to explore the mechanism of Callicarpa kwangtungensis Chun in ameliorating Alzheimer's disease pathology in APP/PS1 mice

ETHNOPHARMACOLOGICAL RELEVANCE

Callicarpa kwangtungensis Chun (CK) is a traditional herb for the treatment of blood stasis, hemostasis, anti-inflammation, and antidepressant. Previous studies have showen that CK extract has significant anti-neuroinflammatory activity. However, the mechanism by which it treats AD is still unclear.

AIM OF STUDY

This study aimed to investigate the effects and mechanisms of CK in ameliorating AD pathology using in vivo and in vitro models, supported by a multi-omics analysis approach.

MATERIALS AND METHODS

The chemical composition of CK was characterized using UPLC-QE Plus-MS/MS. The effects and mechanisms of CK on AD pathology were then investigated using APP/PS1 mice and BV2 and HT22 cell models, with comprehensive insights provided by network pharmacology, transcriptomics, and metabolomics analyses.

RESULTS

This study is the first to report the identification of 146 compounds from CK. CK administration led to significant improvements in cognitive function, reduced amyloid-beta and neurofibrillary tangle formation, and inhibited the activation of microglia and astrocytes in APP/PS1 mice. Comprehensive analyses suggest that CK may modulate the TCA cycle through the PI3K-AKT signaling pathways and inflammation-related MAPK and NF-κB signaling pathways. In vitro studies revealed that CK significantly inhibited LPS-induced inflammation and oxidative stress in BV2 cells, as well as reduced oxidative stress and neuronal apoptosis in HT22 cells.

CONCLUSION

These findings underscore the potential of CK as a therapeutic agent in alleviating AD pathology. This study offers new insights into CK's mechanisms, suggesting that its therapeutic effects may be achieved through the coordinated reduction of neuroinflammation, oxidative stress, and neuronal apoptosis across multiple pathways, collectively working to counteract AD pathology.

Unlocking the neuroprotective potential of Ziziphora clinopodioides flavonoids in combating neurodegenerative diseases and other brain injuries

Ziziphora clinopodioides Lam. (Z. clinopodioides) is a traditional Chinese and ethnic medicine in Xinjiang, China with various therapeutic effects. It is primarily used for conditions such as heart disease, fever with chills, palpitations, and insomnia. Flavonoids are the main medicinal components of Z. clinopodioides, Interestingly, current research has increasingly focused on its neuroprotective effects. This study provides a comprehensive overview of the potential therapeutic applications of Z. clinopodioides and its constituents in central nervous system disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and cerebral ischemia-reperfusion injury. At present, about 25 flavonoids have been isolated and identified from various organs of Z. clinopodioides, including linarin, acacetin, hyperoside, quercetin, apigenin, luteolin, chrysin, kaempferol, baicalein, rutin and others. Modern pharmacological studies have revealed that Z. clinopodioides and its constituents exhibits neuroprotective effects in vitro and in vivo, and the mechanism of action is related to anti-apoptosis, anti-inflammatory, antioxidant, autophagy, endoplasmic reticulum stress and so on. Currently, there is limited research on the extracts of Z. clinopodioides and their potential mechanisms of action in these neurological disorders. It is also important to prioritize research on biosynthetic pathways and chemical modification approaches to fully explore and improve the neuroprotective potential of Z. clinopodioides and its flavonoids and establish a strong foundation for its clinical applications.

Antioxidative and Anticancer Potential of Luteolin: A Comprehensive Approach Against Wide Range of Human Malignancies

Luteolin is widely distributed phytochemical, a flavonoid, in kingdom plantae. Luteolin with potential antioxidant activity prevent ROS-induced damages and reduce oxidative stress which is mainly responsible in pathogenesis of many diseases. Several chemo preventive activities and therapeutic benefits are associated with luteolin. Luteolin prevents cancer via modulation of numerous pathways, that is, by inactivating proteins; such as procaspase-9, CDC2 and cyclin B or upregulation of caspase-9 and caspase-3, cytochrome C, cyclin A, CDK2, and APAF-1, in turn inducing cell cycle arrest as well as apoptosis. It also enhances phosphorylation of p53 and expression level of p53-targeted downstream gene. By Increasing BAX protein expression; decreasing VEGF and Bcl-2 expression it can initiate cell cycle arrest and apoptosis. Luteolin can stimulate mitochondrial-modulated functions to cause cellular death. It can also reduce expression levels of p-Akt, p-EGFR, p-Erk1/2, and p-STAT3. Luteolin plays positive role against cardiovascular disorders by improving cardiac function, decreasing the release of inflammatory cytokines and cardiac enzymes, prevention of cardiac fibrosis and hypertrophy; enhances level of CTGF, TGFβ1, ANP, Nox2, Nox4 gene expressions. Meanwhile suppresses TGFβ1 expression and phosphorylation of JNK. Luteolin helps fight diabetes via inhibition of alpha-glucosidase and ChE activity. It can reduce activity levels of catalase, superoxide dismutase, and GS4. It can improve blood glucose, insulin, HOMA-IR, and HbA1c levels. This review is an attempt to elaborate molecular targets of luteolin and its role in modulating irregularities in cellular pathways to overcome severe outcomes during diseases including cancer, cardiovascular disorders, diabetes, obesity, inflammation, Alzheimer's disease, Parkinson's disease, hepatic disorders, renal disorders, brain injury, and asthma. As luteolin has enormous therapeutic benefits, it could be a potential candidate in future drug development strategies.

Inhibitory Effects of Gliadin Hydrolysates on BACE1 Expression and APP Processing to Prevent Aβ Aggregation

Alzheimer's disease (AD), a leading neurodegenerative disorder, is closely associated with the accumulation of amyloid-beta (Aβ) peptides in the brain. The enzyme β-secretase (BACE1), pivotal in Aβ production, represents a promising therapeutic target for AD. While bioactive peptides derived from food protein hydrolysates have neuroprotective properties, their inhibitory effects on BACE1 remain largely unexplored. In this study, we evaluated the inhibitory potential of protein hydrolysates from gliadin, whey, and casein proteins prepared using bromelain, papain, and thermolysin. Through in vitro and cellular assays, bromelain-hydrolyzed gliadin (G-Bro) emerged as the most potent BACE1 inhibitor, with an IC50 of 0.408 mg/mL. G-Bro significantly reduced BACE1 expression and amyloid precursor protein (APP) processing in N2a/PS/APP cell cultures, suggesting its potential to attenuate Aβ aggregation. The unique peptide profile of G-Bro likely contributes to its inhibitory effect, with proline residues disrupting β-sheets, lysine residues introducing positive charges that hinder aggregation, hydrophobic residues stabilizing binding interactions, and glutamine residues enhancing solubility and stability. These findings highlight gliadin hydrolysates, particularly G-Bro, as potential natural BACE1 inhibitors with applications in dietary interventions for AD prevention. However, further studies are warranted to elucidate specific peptide interactions and their bioactivity in neural pathways to better understand their therapeutic potential.

Kaixinsan regulates neuronal mitochondrial homeostasis to improve the cognitive function of Alzheimer's disease by activating CaMKKβ-AMPK-PGC-1α signaling axis

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease primarily characterized by cognitive impairments. With the intensification of population aging, AD has become a major health concern affecting the elderly. Kaixinsan, a classical traditional Chinese formula, consists of Ginseng Panax et Rhizoma, Polygalae Radix, Poria and Acori Tatarinowii Rhizoma, and is commonly used in clinical for treating memory decline. However, its mechanism remains unclear, which hinders its popularization and application.

METHOD

Morris water maze (MWM) was performed to evaluate the effect of Kaixinsan on improving learning and memory ability in SAMP8 (senescence-accelerated mouse prone 8, an AD model mice) mice. Nissl staining, TdT-mediated dUTP Nick End Labeling (TUNEL) and western blotting (Bax and Bcl-2) were used to confirm the effect of Kaixinsan on the neuronal structure and apoptosis of SAMP8 mice. Ultra performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (UPLC-Q-TOF/MS) was performed to identify the distribution components in brain tissue after administration of Kaixinsan extraction. Based on the identified brain distribution components, the mechanism of Kaixinsan improving the cognitive function was predicted by network pharmacology. Then, using HSP60 as a mitochondrial marker and RBFOX3 as a neuronal marker, immunofluorescence co-localization was used to confirm the effect of Kaixinsan on neuronal mitochondria quantity in SAMP8 mice. Western blotting was employed to access the expression of predicted proteins (AMPK, CaMKKβ, PGC-1α and HSP90) implicated in mitochondrial homeostasis. To further confirm the mechanism of Kaixinsan, SH-SY5Y cell injury model induced by amyloid β - protein fragment 25-35 (Aβ25-35) was replicated and the effect of Kaixinsan - containing serum on apoptosis in injured SH-SY5Y cells was investigated by flow cytometer. The expression level of apoptosis-associated proteins (Bax and Bcl-2) and mitochondrial homeostasis related proteins (AMPK, CaMKKβ, PGC-1α and HSP90) in the presence or absence of CaMKKβ inhibitor (STO-609) were compared.

RESULTS

The results indicate that Kaixinsan can improve the cognitive function of SAMP8 mice, alleviate the hippocampal tissue lesions and inhibit neuron apoptosis. Seventeen brain distribution components of Kaixinsan were identified. Based on the brain distribution components of Kaixinsan, the results of network pharmacology suggest that Kaixinsan may regulate mitochondrial homeostasis through the CaMKKβ-AMPK-PGC-1α signaling axis. In vivo experiments indicated that Kaixinsan could reverse neuronal mitochondrial loss in SAMP8 mice by upregulating CaMKKβ, AMPK, HSP90 and PGC-1α to promote mitochondrial biogenesis and increase the number of neuronal mitochondria. Additionally, the in vitro experiments demonstrated that Kaixinsan can inhibit apoptosis of Aβ25-35 injured SH-SY5Y cells and upregulate mitochondrial homeostasis-related proteins CaMKKβ, AMPK and PGC-1α. However, in addition to CaMKKβ inhibitors, the neuroprotective effect disappeared.

CONCLUSION

The results indicate that Kaixinsan can improve the cognitive function of SAMP8 mice by regulating CaMKKβ-AMPK-PGC-1α signaling axis to maintain mitochondrial homeostasis and inhibit neuronal apoptosis.

The potential therapeutic strategy in combating neurodegenerative diseases: Focusing on natural products

Neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS), Huntington disease (HD), and Multiple sclerosis (MS), pose a significant global health challenge due to their intricate pathology and limited therapeutic interventions. Natural products represent invaluable reservoirs for combating these neurodegenerative diseases by targeting key pathological hallmarks such as protein aggregation, synaptic dysfunction, aberrant proteostasis, cytoskeletal abnormalities, altered energy homeostasis, inflammation, and neuronal cell death. This review provides an in-depth analysis of the mechanisms and therapeutic targets of natural products for their neuroprotective effects. Furthermore, it elucidates the current progress of clinical trials investigating the potential of natural products in delaying neurodegeneration. The objective of this review is to enhance the comprehension of natural products in the prevention and treatment of neurodegenerative diseases, offering new insights and potential avenues for future pharmaceutical research.

Establishing network pharmacology between natural polyphenols and Alzheimer's disease using bioinformatic tools - An advancement in Alzheimer's research

Alzheimer's disease (AD) is a major cause of disability and one of the top causes of mortality globally. AD remains a major public health challenge due to its prevalence, impact on patients and caregivers, and the current lack of a cure. In recent years, polyphenols have garnered attention for their potential therapeutic effects on AD. The objective of the study was to establish network pharmacology between selected polyphenols of plant origin and AD. Insilico tools such as SwissADME, ProTox3.0, pkCSM, Swiss Target Prediction, DisGeNET, InterActiVenn, DAVID database, STRING database, Cytoscape/CytoHubba were employed to establish the multi-target potential of the polyphenolic compounds. The present study revealed that out of 17 polyphenols, 10 ligands were found to possess a drug-likeness nature along with desirable pharmacokinetic parameters and a lesser toxicity profile. Also, the results highlighted the possible interactions between the polyphenols and the disease targets involved in AD. Further, this study has shed light on the mTOR pathway and its impact on AD through the autophagic mechanism. Overall, this study indicated that polyphenols could be a better therapeutic option for treating AD. Hence, the consumption of polyphenolic cocktails as a part of the diet could produce more effective outcomes against the disease. Additional studies are warranted in the future to explore additional pathways and genes to provide a comprehensive understanding regarding the usage of the shortlisted polyphenols and their derivatives for the prevention and treatment of AD.

Mitochondrial dysfunction as a therapeutic strategy for neurodegenerative diseases: Current insights and future directions

Neurodegenerative diseases, as common diseases in the elderly, tend to become younger due to environmental changes, social development and other factors. They are mainly characterized by progressive loss or dysfunction of neurons in the central or peripheral nervous system, and common diseases include Parkinson's disease, Alzheimer's disease, Huntington's disease and so on. Mitochondria are important organelles for adenosine triphosphate (ATP) production in the brain. In recent years, a large amount of evidence has shown that mitochondrial dysfunction plays a direct role in neurodegenerative diseases, which is expected to provide new ideas for the treatment of related diseases. This review will summarize the main mechanisms of mitochondrial dysfunction in neurodegenerative diseases, as well as collating recent advances in the study of mitochondrial disorders and new therapies.

Unveiling the molecular mechanisms of Danggui-Shaoyao-San against Alzheimer's disease in APP/PS1 mice via integrating proteomic and metabolomic approaches

BACKGROUND

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder for which no effective therapy is currently available. Given that various attempts to target beta-amyloid (Aβ) have been unsuccessful in clinical trials, other potential pathogenic factors such as brain energy metabolism (EM) have attracted increasing attention. Traditional Chinese medicines, including danggui-shaoyao-san (DSS), play a notable role in AD. However, it remains unclear whether DSS exerts therapeutic effects on AD through EM regulation.

METHODS

In this study, we conducted behavioural tests, Nissl staining, haematoxylin and eosin staining, and thioflavin S staining, in APP/PS1 mice to assess the pharmacodynamic effect of DSS on AD. Subsequently, we integrated the drug target network of herbal ingredients in DSS and evaluated their absorption, distribution, metabolism, excretion, and toxicity properties to identify the core ingredients. We used proteomic and metabolomic approaches to explore the potential mechanisms of action of DSS against AD. Consequently, we verified the mechanism underlying EM using qPCR, western blotting, and ELISA.

RESULTS

In vivo experimental results revealed that DSS ameliorated cognitive impairment in APP/PS1 mice, attenuated neuronal apoptosis, and reduced Aβ burden. Furthermore, the drug-target network comprised 6,514 drug-target interactions involving 1,118 herbal ingredients and 218 AD genes, of which 253 were identified as the core ingredients in DSS. The proteomic results implied that DSS could act on EM to alleviate AD, and targeted energy metabolomics suggested that DSS regulated 47 metabolites associated with EM. Mechanistically, we found that DSS could regulate the GSK3β/PGC1α signalling pathway to improve brain glucose uptake and mitigate mitochondrial dysfunction and oxidative stress, ultimately promoting EM to treat AD.

CONCLUSION

Our study is the first to integrate multi-omics approaches to reveal that DSS could regulate the GSK3β/PGC1α signalling pathway to exert therapeutic effects in AD through the promotion of EM, thereby providing new insights into the mechanism of action of DSS against AD.

Prevention and Treatment of Alzheimer's Disease Via the Regulation of the Gut Microbiota With Traditional Chinese Medicine

Alzheimer's disease (AD) is caused by a variety of factors, and one of the most important factors is gut microbiota dysbiosis. An imbalance in the gut mincrobiota have been shown to change the concentrations of lipopolysaccharide and short-chain fatty acids. These microorganisms synthesize substances that can influence the levels of a variety of metabolites and cause multiple diseases through the immune response, fatty acid metabolism, and amino acid metabolism pathways. Furthermore, these metabolic changes promote the formation of β-amyloid plaques and neurofibrillary tangles. Thus, the microbiota-gut-brain axis plays an important role in AD development. In addition to traditional therapeutic drugs such as donepezil and memantine, traditional Chinese medicines (TCMs) have also showed to significantly decrease the severity of AD symptoms and suppress the underlying related mechanisms. We searched for studies on the effects of different herbal monomers, single herbs, and polyherbal formulas on the gut microbiota of AD patients and identified the relevant pathways through which the gut microbiota affected AD. We conclude that improvements in the gut microbiota not only decrease the occurrence of inflammatory reactions but also reduce the deposition of central pathological products. Herbal monomers have a stronger effect on improving of central pathology. Polyherbal formulas have the most extensive effect on the gut microbiota in patients with AD. Among the effects of formulas, the anti-inflammatory effect is the most essential and is also the main concern regarding the use of TCMs in treating AD from the viewpoint of the gut microbiota. We hope that this review will be helpful for providing new ideas for the clinical application of TCMs in the treatment of AD.

Luteolin protects against myocardial ischemia/reperfusion injury by reducing oxidative stress and apoptosis through the p53 pathway

OBJECTIVE

Myocardial ischemia/reperfusion injury (MIRI) is an obstacle to the success of cardiac reperfusion therapy. This study explores whether luteolin can mitigate MIRI by regulating the p53 signaling pathway.

METHODS

Model mice were subjected to a temporary surgical ligation of the left anterior descending coronary artery, and administered luteolin. The myocardial infarct size, myocardial enzyme levels, and cardiac function were measured. Latent targets and signaling pathways were screened using network pharmacology and molecular docking. Then, proteins related to the p53 signaling pathway, apoptosis and oxidative stress were measured. Hypoxia/reoxygenation (HR)-incubated HL1 cells were used to validate the effects of luteolin in vitro. In addition, a p53 agonist and an inhibitor were used to investigate the mechanism.

RESULTS

Luteolin reduced the myocardial infarcted size and myocardial enzymes, and restored cardiac function in MIRI mice. Network pharmacology identified p53 as a hub target. The bioinformatic analyses showed that luteolin had anti-apoptotic and anti-oxidative properties. Additionally, luteolin halted the activation of p53, and prevented both apoptosis and oxidative stress in myocardial tissue in vivo. Furthermore, luteolin inhibited cell apoptosis, JC-1 monomer formation, and reactive oxygen species elevation in HR-incubated HL1 cells in vitro. Finally, the p53 agonist NSC319726 downregulated the protective attributes of luteolin in the MIRI mouse model, and both luteolin and the p53 inhibitor pifithrin-α demonstrated a similar therapeutic effect in the MIRI mice.

CONCLUSION

Luteolin effectively treats MIRI and may ameliorate myocardial damage by regulating apoptosis and oxidative stress through its targeting of the p53 signaling pathway. Please cite this article as: Zhai P, Ouyang XH, Yang ML, Lin L, Li JY, Li YM, Cheng X, Zhu R, Hu DS. Luteolin protects against myocardial ischemia/reperfusion injury by reducing oxidative stress and apoptosis through the p53 pathway. J Integr Med. 2024; 22(6): 652-664.

Response Surface Methodology Optimization of Exosome-like Nanovesicles Extraction from Lycium ruthenicum Murray and Their Inhibitory Effects on Aβ-Induced Apoptosis and Oxidative Stress in HT22 Cells

Exosome-like nanovesicles (ELNs) derived from plants are nanoscale vesicles isolated from edible plant sources. Lycium ruthenicum Murray (LRM) has garnered growing attention for its dietary value and therapeutic benefits. In this study, a PEG6000-based method was developed to isolate LRM-ELNs. Response surface methodology (RSM) was used to optimize the extraction conditions to obtain the optimal extraction efficiency. When PEG6000 concentration was at 11.93%, relative centrifugal force was 9720 g, and incubation time was 21.12 h, the maximum LRM-ELN yield was 4.24 g/kg. This optimization process yielded LRM-ELNs with a particle size of 114.1 nm and a surface charge of -6.36 mV. Additionally, LRM-ELNs mitigated Aβ-induced apoptosis in HT22 cells by enhancing mitochondrial membrane potential (MMP), lowering the Bax/Bcl-2 ratio, and reducing Cleaved Caspase-3 expression. Furthermore, LRM-ELNs alleviated Aβ-induced oxidative stress in HT22 cells by promoting the nuclear translocation of Nrf2 and upregulating the expression of HO-1 and NQO1. These findings indicate that LRM-ELNs exert protective effects against Aβ-induced damage in HT22 cells and may be considered as a potential dietary supplement for Alzheimer's disease prevention.

Pathogenesis of Alzheimer's disease and therapeutic strategies involving traditional Chinese medicine

Alzheimer's disease (AD) is a prevalent degenerative disorder affecting the central nervous system of the elderly. Patients primarily manifest cognitive decline and non-cognitive neuro-psychiatric symptoms. Currently, western medications for AD primarily include cholinesterase inhibitors and glutamate receptor inhibitors, which have limited efficacy and accompanied by significant toxic side effects. Given the intricate pathogenesis of AD, the use of single-target inhibitors is limited. In recent years, as research on AD has progressed, traditional Chinese medicine (TCM) and its active ingredients have increasingly played a crucial role in clinical treatment. Numerous studies demonstrate that TCM and its active ingredients can exert anti-Alzheimer's effects by modulating pathological protein production and deposition, inhibiting tau protein hyperphosphorylation, apoptosis, inflammation, and oxidative stress, while enhancing the central cholinergic system, protecting neurons and synapses, and optimizing energy metabolism. This article summarizes extracts from TCM and briefly elucidates their pharmacological mechanisms against AD, aiming to provide a foundation for further research into the specific mechanisms of TCM in the prevention and treatment of the disease, as well as the identification of efficacious active ingredients.

Luteolin Mitigates D-Galactose-Induced Brain Ageing in Rats: SIRT1-Mediated Neuroprotection

Luteolin is an essential natural polyphenol found in a variety of plants. Numerous studies have supported its protective role in neurodegenerative diseases, yet the research for its therapeutic utility in D-galactose (D-gal)-induced brain ageing is still lacking. In this study, the potential neuroprotective impact of luteolin against D-gal-induced brain ageing was explored. Forty rats were randomly divided into four groups: control, luteolin, D-gal, and luteolin-administered D-gal groups. All groups were subjected to behavioural, cholinergic function, and hippocampal mitochondrial respiration assessments. Hippocampal oxidative, neuro-inflammatory, senescence and apoptotic indicators were detected. Gene expressions of SIRT1, BDNF, and RAGE were assessed. Hippocampal histopathological studies, along with GFAP and Ki67 immunoreactivity, were performed. Our results demonstrated that luteolin effectively alleviated D-gal-induced cognitive impairment and reversed cholinergic abnormalities. Furthermore, luteolin administration substantially mitigated hippocampus oxidative stress, mitochondrial dysfunction, neuro-inflammation, and senescence triggered by D-gal. Additionally, luteolin treatment considerably attenuated neuronal apoptosis and upregulated hippocampal SIRT1 mRNA expression. In conclusion, our findings revealed that luteolin administration attenuated D-gal-evoked brain senescence, improving mitochondrial function and enhancing hippocampal neuroregeneration in an ageing rat model through its antioxidant, senolytic, anti-inflammatory, and anti-apoptotic impacts, possibly due to upregulation of SIRT1. Luteolin could be a promising therapeutic modality for brain aging-associated abnormalities.

Luteolin as potential treatment for Huntington's disease: Insights from a transgenic mouse model

AIMS

The study aimed to evaluate the potential benefits of luteolin treatment in Huntington's disease (HD), an inherited progressive neurodegenerative disorder.

METHODS

HD N171-82Q transgenic and WT mice received luteolin or vehicle for treatment at 6 weeks of age. The mice's body weight changes and survival rates were monitored throughout the study, and a series of motor functional tests were conducted. Serum level of the marker NfL was also determined. Immunohistochemical staining and western blotting were utilized to assess the expression of huntingtin aggregates.

RESULTS

Luteolin treatment enhanced survival and prevented weight loss in HD mice compared to the vehicle-treated HD group. Furthermore, the luteolin-treated HD mice exhibited enhanced motor coordination and balance and significantly reduced motor dysfunction. Also, luteolin decreased serum NfL levels in HD mice. Notably, the accumulation of huntingtin aggregates was significantly reduced in the brain's cortex, hippocampus, and striatum of luteolin-treated HD mice compared to the vehicle-treated HD group.

CONCLUSION

Luteolin holds promise as a therapeutic agent for improving survival outcomes, managing motor dysfunction, and reducing huntingtin aggregates in HD. The findings are of significance as currently, there are no approved therapeutic interventions that reverse HD pathology or slow down its progression.

Polysaccharides extracted from common buckwheat (Fagopyrum esculentum) attenuate cognitive impairment via suppressing RAGE/p38/NF-κB signaling and dysbiosis in AlCl3-treated rats

Patients may find it challenging to accept several FDA-approved drugs for Alzheimer's disease (AD) treatment due to their unaffordable prices and side effects. Despite the known antioxidant, anti-inflammatory, and microbiota-regulating effects of common buckwheat (Fagopyrum esculentum) polysaccharides (FEP), their specific role in preventing AD has not been determined. Here, this study investigated the preventive effects of FEP on AD development in AlCl3-treated rats. The physical properties of FEP were evaluated using X-ray diffraction, FTIR, TGA, DSC, monosaccharide composition, molecular weight, and scanning electron microscopy. The results demonstrated that FEP administration improved memory and learning ability in AlCl3-treated rats. Additionally, AD pathological biomarkers (APP, BACE1, Aβ1-42, and p-TauSer404), inflammatory-associated proteins (IL-1β, IL-6, TNF-α, and Iba1), and MDA and the RAGE/p38/NF-κB pathway were elevated in AlCl3-treated rats. Moreover, these effects were reversed by the upregulation of LRP1, anti-inflammatory cytokines (IL-4 and IL-10), antioxidant enzymes (SOD and catalase), and autophagy proteins (Atg5, Beclin-1, and LC3B). Furthermore, FEP treatment increased the levels of short-chain fatty acids (SCFAs) and the abundance of SCFAs-producing microbes ([Eubacterium]_xylanophilum_group, Lachnospiraceae_NK4A136_group, Lactobacillus). Overall, FEP mitigated oxidative stress, RAGE/p38/NF-κB-mediated neuroinflammation, and AD-associated proteins by upregulating autophagy and SCFA levels, which led to the amelioration of cognitive impairment through microbiota-gut-brain communication in AlCl3-treated rats.

Network pharmacology- and molecular docking-based investigation on the mechanism of action of Si-ni San in the treatment of depression combined with anxiety and experimental verification in adolescent rats

Background

The incidence rate of adolescent depression and anxiety has been increasing since the outbreak of COVID-19, which there are no effective therapeutic drugs available. Si-ni San is commonly used in traditional Chinese medicine for the treatment of depression-like as well as anxiety-like behavior, but its mechanism for treating depression combined with anxiety during adolescence is not yet clear.

Methods

Network pharmacology was used to explore potential drug molecules and related targets, molecular docking and molecular dynamics (MD) simulation were used to evaluate the interaction between the potential drug molecules and related targets, and a model of anxiety combined with depression in adolescent rats as well as the following behavioral tests and molecular biology tests were used to verify the results from network pharmacology and molecular docking.

Results

As a result, 256 active ingredients of Si-ni San and 1128 potential targets were screened out. Among them, quercetin, Luteolin, kaempferol, 7-Methoxy-2-methyl isoflavone, formononetin showed to be the most potential ingredients; while STAT3, IL6, TNF, AKT1, AKT1, TP53, IL1B, MAPK3, VEGFA, CASP3, MMP9 showed to be the most potential targets. AGE-RAGE signaling pathway in diabetic complications, IL-17 signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway and TNF signaling pathway, which are involved in anti-inflammation processes, showed to be the most probable pathways regulated by Si-ni San. Molecular docking and MD simulation between the compounds to inflammation-associated targets revealed good binding abilities of quercetin, Luteolin, kaempferol, nobiletin and formononetin to PTGS2 and PPARγ. In the experiment with adolescent rats, Si-ni San markedly suppressed early maternal separation (MS) combined with adolescent chronic unpredictable mild stress (CUMS)-induced depression combined with anxiety. The qPCR results further indicated that Si-ni San regulated the oxidative stress and inflammatory response.

Conclusion

This study demonstrates that adolescent anxiety- and depression-like behavior induced by MS combined CUMS can be ameliorated by Si-ni San by improved inflammation in hippocampus via targeting TNF pathway and Nrf2 pathway, helping to reveal the mechanism of Si-ni San in treating adolescent depression combined with anxiety.