Suppression of 6-Hydroxydopamine-Induced Oxidative Stress by Hyperoside Via Activation of Nrf2/HO-1 Signaling in Dopaminergic Neurons

Chinese medicine PaBing-II protects human iPSC-derived dopaminergic neurons from oxidative stress

Background

PaBing-II Formula (PB-II) is a traditional Chinese medicine for treating Parkinson's disease (PD). However, owing to the complexity of PB-II and the difficulty in obtaining human dopaminergic neurons (DAn), the mechanism of action of PB-II in PD treatment remains unclear. The aim of this study was to investigate the mechanisms underlying the therapeutic benefits of PB-II in patients with PD.

Methods

hiPSCs derived DAn were treated with H2O2 to construct the DAn oxidative damage model. SwissTargetPrediction was employed to predict the potential targets of the main compounds in serum after PB-II treatment. Metascape was used to analyze the pathways. Sprague-Dawley rats were used to construct the 6-hydroxydopamine (6-OHDA)-induced PD model, and the duration of administration was four weeks. RNA sequencing was used for Transcriptome analysis to find the signal pathways related to neuronal damage. The associated inflammatory factors were detected by enzyme-linked immunosorbent assay (ELISA). We identified PB-II as an Nrf2 activator using antioxidant-responsive element luciferase assay in MDA-MB-231 cells.

Results

In vitro experiments showed that the treatment of PB-II-treated serum increased the percentage of TH+ cells, decreased inflammation and the apoptosis, reduced cellular reactive oxygen species, and upregulated the expression of Nrf2 and its downstream genes. Pathway analysis of the RNA-seq data of samples before and after the treatment with PB-II-treated serum identified neuron-associated pathways. In vivo experiments demonstrated that PB-II treatment of PD rat model could activate the Nrf2 signaling pathway, protect the midbrain DAn, and improve the symptoms in PD rats.

Conclusion

PB-II significantly protects DAn from inflammation and oxidative stress via Nrf2 pathway activation. These findings elucidate the roles of PB-II in PD treatment and demonstrate the application of hiPSC-derived DAn in research of Chinese medicine.

Transgenerational hormesis in healthy aging and antiaging medicine from bench to clinics: Role of food components

Neurodegenerative diseases have multifactorial pathogenesis, mainly involving neuroinflammatory processes. Finding drugs able to treat these diseases, expecially because for most of these diseases there are no effective drugs, and the current drugs cause undesired side effects, represent a crucial point. Most in vivo and in vitro studies have been concentrated on various aspects related to neurons (e.g. neuroprotection), however, there has not been focus on the prevention of early stages involving glial cell activation and neuroinflammation. Recently, it has been demonstrated that nutritional phytochemicals including polyphenols, the main active constituents of the Mediterranean diet, maintain redox balance and neuroprotection through the activation of hormetic vitagene pathway. Recent lipidomics data from our laboratory indicate mushrooms as strong nutritional neuronutrients with strongly activity against neuroinflammation in Meniere' diseaseas, a model of cochleovestibular neural degeneration, as well as in animal model of traumatic brain injury, or rotenone induced parkinson's disease. Moreover, Hidrox®, an aqueous extract of olive containing hydroxytyrosol, and Boswellia, acting as Nrf2 activators, promote resilience by enhancing the redox potential, and thus, regulate through hormetic mechanisms, cellular stress response mechanisms., Thus, modulation of cellular stress pathways, in particular vitagenes system, may be an innovative approach for therapeutic intervention in neurodegenerative disorders.

Ergothioneine-Mediated Neuroprotection of Human iPSC-Derived Dopaminergic Neurons

Cell death involving oxidative stress and mitochondrial dysfunction is a major cause of dopaminergic neuronal loss in the substantia nigra (SN) of Parkinson's disease patients. Ergothioneine (ET), a natural dietary compound, has been shown to have cytoprotective functions, but neuroprotective actions against PD have not been well established. 6-Hydroxydopamine (6-OHDA) is a widely used neurotoxin to simulate the degeneration of dopaminergic (DA) neurons in Parkinson's disease. In this study, we investigated the protective effect of ET on 6-OHDA treated iPSC-derived dopaminergic neurons (iDAs) and further confirmed the protective effects in 6-OHDA-treated human neuroblastoma SH-SY5Y cells. In 6-OHDA-treated cells, decreased mitochondrial membrane potential (ΔΨm), increased mitochondrial reactive oxygen species (mROS), reduced cellular ATP levels, and increased total protein carbonylation levels were observed. 6-OHDA treatment also significantly decreased tyrosine hydroxylase levels. These effects were significantly decreased when ET was present. Verapamil hydrochloride (VHCL), a non-specific inhibitor of the ET transporter OCTN1 abrogated ET's cytoprotective effects, indicative of an intracellular action. These results suggest that ET could be a potential therapeutic for Parkinson's disease.

Hyperoside inhibits EHV-8 infection via alleviating oxidative stress and IFN production through activating JNK/Keap1/Nrf2/HO-1 signaling pathways

Equine herpesvirus type 8 (EHV-8) causes abortion and respiratory disease in horses and donkeys, leading to serious economic losses in the global equine industry. Currently, there is no effective vaccine or drug against EHV-8 infection, underscoring the need for a novel antiviral drug to prevent EHV-8-induced latent infection and decrease the pathogenicity of this virus. The present study demonstrated that hyperoside can exert antiviral effects against EHV-8 infection in RK-13 (rabbit kidney cells), MDBK (Madin-Darby bovine kidney), and NBL-6 cells (E. Derm cells). Mechanistic investigations revealed that hyperoside induces heme oxygenase-1 expression by activating the c-Jun N-terminal kinase/nuclear factor erythroid-2-related factor 2/Kelch-like ECH-associated protein 1 axis, alleviating oxidative stress and triggering a downstream antiviral interferon response. Accordingly, hyperoside inhibits EHV-8 infection. Meanwhile, hyperoside can also mitigate EHV-8-induced injury in the lungs of infected mice. These results indicate that hyperoside may serve as a novel antiviral agent against EHV-8 infection.IMPORTANCEHyperoside has been reported to suppress viral infections, including herpesvirus, hepatitis B virus, infectious bronchitis virus, and severe acute respiratory syndrome coronavirus 2 infection. However, its mechanism of action against equine herpesvirus type 8 (EHV-8) is currently unknown. Here, we demonstrated that hyperoside significantly inhibits EHV-8 adsorption and internalization in susceptible cells. This process induces HO-1 expression via c-Jun N-terminal kinase/nuclear factor erythroid-2-related factor 2/Kelch-like ECH-associated protein 1 axis activation, alleviating oxidative stress and triggering an antiviral interferon response. These findings indicate that hyperoside could be very effective as a drug against EHV-8.

Therapeutic potential of salidroside in preserving rat cochlea organ of corti from gentamicin-induced injury through modulation of NRF2 signaling and GSK3β/NF-κB pathway

Salidroside (SAL) is a phenol glycoside compound found in plants of the Rhodiola genus which has natural antioxidant and free radical scavenging properties. SAL are able to protect against manganese-induced ototoxicity. However, the molecular mechanism by which SAL reduces levels of reactive oxygen species (ROS) is unclear. Here, we established an in vitro gentamicin (GM) ototoxicity model to observe the protective effect of SAL on GM-induced hair cells (HC) damage. Cochlear explants of postnatal day 4 rats were obtained and randomly divided into six groups: two model groups (treatment with 0.2 mM or 0.4 mM GM for 24 h); two 400 μmol/L SAL-pretreated groups pretreatment with SAL for 3 h followed by GM treatment (0.2 mM or 0.4 mM) for 24 h; 400 μmol/L SAL group (treatment with SAL for 24 h); control group (normal cultured cochlear explants). The protective effects of SAL on GM-induced HC damage, and on mRNA and protein levels of antioxidant enzymes were observed. HC loss occurred after 24 h of GM treatment. Pretreatment with SAL significantly reduced GM-induced OHC loss. In cochlear tissues, mRNA and protein levels of NRF2 and HO-1 were enhanced in the GM alone group compared with the SAL pretreatment GM treatment group. SAL may protect against GM-induced ototoxicity by regulating the antioxidant defense system of cochlear tissues; SAL can activate NRF2/HO-1 signaling, inhibit NF-κB activation, activate AKT, and increase inhibitory phosphorylation of GSK3β to decrease GSK3 activity, all of which exert antioxidant effects.

Ferroptosis regulation through Nrf2 and implications for neurodegenerative diseases

This article provides an overview of the background knowledge of ferroptosis in the nervous system, as well as the key role of nuclear factor E2-related factor 2 (Nrf2) in regulating ferroptosis. The article takes Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) as the starting point to explore the close association between Nrf2 and ferroptosis, which is of clear and significant importance for understanding the mechanism of neurodegenerative diseases (NDs) based on oxidative stress (OS). Accumulating evidence links ferroptosis to the pathogenesis of NDs. As the disease progresses, damage to the antioxidant system, excessive OS, and altered Nrf2 expression levels, especially the inhibition of ferroptosis by lipid peroxidation inhibitors and adaptive enhancement of Nrf2 signaling, demonstrate the potential clinical significance of Nrf2 in detecting and identifying ferroptosis, as well as targeted therapy for neuronal loss and mitochondrial dysfunction. These findings provide new insights and possibilities for the treatment and prevention of NDs.

Role of Natural Compounds Modulating Heme Catabolic Pathway in Gut, Liver, Cardiovascular, and Brain Diseases

The crucial physiological process of heme breakdown yields biliverdin (BV) and bilirubin (BR) as byproducts. BV, BR, and the enzymes involved in their production (the "yellow players-YP") are increasingly documented as endogenous modulators of human health. Mildly elevated serum bilirubin concentration has been correlated with a reduced risk of multiple chronic pro-oxidant and pro-inflammatory diseases, especially in the elderly. BR and BV per se have been demonstrated to protect against neurodegenerative diseases, in which heme oxygenase (HMOX), the main enzyme in the production of pigments, is almost always altered. HMOX upregulation has been interpreted as a tentative defense against the ongoing pathologic mechanisms. With the demonstration that multiple cells possess YP, their propensity to be modulated, and their broad spectrum of activity on multiple signaling pathways, the YP have assumed the role of an adjustable system that can promote health in adults. Based on that, there is an ongoing effort to induce their activity as a therapeutic option, and natural compounds are an attractive alternative to the goal, possibly requiring only minimal changes in the life style. We review the most recent evidence of the potential of natural compounds in targeting the YP in the context of the most common pathologic condition of adult and elderly life.

Hyperoside Inhibits RNF8-mediated Nuclear Translocation of β-catenin to Repress PD-L1 Expression and Prostate Cancer

BACKGROUND

Hyperoside is a flavonol glycoside isolated from Hypericum perforatum L. that has inhibitory effects on cancer cells; however, its effects on prostate cancer (PCa) remain unclear. Therefore, we studied the anti-PCa effects of hyperoside and its underlying mechanisms in vitro and in vivo.

AIM

This study aimed to explore the mechanism of hyperoside in anti-PCa.

METHODS

3-(4,5-Dimethyl-2-Thiazolyl)-2,5-Diphenyl Tetrazolium Bromide (MTT), transwell, and flow cytometry assays were used to detect PCa cell growth, invasion, and cell apoptosis. Immunoblot analysis, immunofluorescence, immunoprecipitation, and quantitative real-time PCR (qRT-PCR) were used to analyze the antitumor mechanism of hyperoside.

RESULTS

Hyperoside inhibited PCa cell growth, invasion, and cell cycle and induced cell apoptosis. Furthermore, RING finger protein 8 (RNF8), an E3 ligase that assembles K63 polyubiquitination chains, was predicted to be a direct target of hyperoside and was downregulated by hyperoside. Downregulation of RNF8 by hyperoside impeded the nuclear translocation of β-catenin and disrupted the Wnt/β-catenin pathway, which reduced the expression of the target genes c-myc, cyclin D1, and programmed death ligand 1 (PD-L1). Decreased PD-L1 levels contributed to induced immunity in Jurkat cells in vitro. Finally, in vivo studies demonstrated that hyperoside significantly reduced tumor size, inhibited PD-L1 and RNF8 expression, and induced apoptosis in tumor tissues of a subcutaneous mouse model.

CONCLUSION

Hyperoside exerts its anti-PCa effect by reducing RNF8 protein, inhibiting nuclear translocation of β-catenin, and disrupting the Wnt/β-catenin pathway, in turn reducing the expression of PD-L1 and improving Jurkat cell immunity.

Evaluating Manganese, Zinc, and Copper Metal Toxicity on SH-SY5Y Cells in Establishing an Idiopathic Parkinson's Disease Model

Parkinson's disease (PD) is a neurodegenerative condition marked by loss of motor coordination and cognitive impairment. According to global estimates, the worldwide prevalence of PD will likely exceed 12 million cases by 2040. PD is primarily associated with genetic factors, while clinically, cases are attributed to idiopathic factors such as environmental or occupational exposure. The heavy metals linked to PD and other neurodegenerative disorders include copper, manganese, and zinc. Chronic exposure to metals induces elevated oxidative stress and disrupts homeostasis, resulting in neuronal death. These metals are suggested to induce idiopathic PD in the literature. This study measures the effects of lethal concentration at 10% cell death (LC10) and lethal concentration at 50% cell death (LC50) concentrations of copper, manganese, and zinc chlorides on SH-SY5Y cells via markers for dopamine, reactive oxygen species (ROS) generation, DNA damage, and mitochondrial dysfunction after a 24 h exposure. These measurements were compared to a known neurotoxin to induce PD, 100 µM 6-hydroxydopamine (6-ODHA). Between the three metal chlorides, zinc was statistically different in all parameters from all other treatments and induced significant dopaminergic loss, DNA damage, and mitochondrial dysfunction. The LC50 of manganese and copper had the most similar response to 6-ODHA in all parameters, while LC10 of manganese and copper responded most like untreated cells. This study suggests that these metal chlorides respond differently from 6-ODHA and each other, suggesting that idiopathic PD utilizes a different mechanism from the classic PD model.

Potential Implications of Hyperoside on Oxidative Stress-Induced Human Diseases: A Comprehensive Review

Hyperoside is a flavonol glycoside mainly found in plants of the genera Hypericum and Crataegus, and also detected in many plant species such as Abelmoschus manihot, Ribes nigrum, Rosa rugosa, Agrostis stolonifera, Apocynum venetum and Nelumbo nucifera. This compound exhibits a multitude of biological functions including anti-inflammatory, antidepressant, antioxidative, vascular protective effects and neuroprotective effects, etc. This review summarizes the quantification, original plant, chemical structure and property, structure-activity relationship, pharmacologic effect, pharmacokinetics, toxicity and clinical application of hyperoside, which will be significant for the exploitation for new drug and full utilization of this compound.

Protective Effects and Mechanisms of Pectolinarin against H2O2-Induced Oxidative Stress in SH-SY5Y Neuronal Cells

This study aims to investigate the protective effects and mechanisms of pectolinarin against oxidative stress-induced cell damage in SH-SY5Y cells. Neurodegenerative diseases-such as Alzheimer's disease-are potentially associated with oxidative stress, which causes excessive production of reactive oxygen species (ROS) that damage DNA and proteins in neuronal cells. The results of this study demonstrate that pectolinarin can scavenge hydroxyl and nitric oxide radicals in a concentration-dependent manner. Moreover, pectolinarin significantly increased cell viability while reducing ROS production and LDH release in the hydrogen peroxide (H2O2)-induced control group. Additionally, Pectolinarin recovered protein expression from H2O2-altered levels back to close-to-normal SH-SY5Y cell levels for components of the oxidative stress, inflammation, and apoptosis pathways-such as nuclear factor erythroid 2-related factor 2 (Nrf2), kelch-like ECH-associated protein (Keap1), anti-heme oxygenase 1 (HO-1), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), B-cell lympho-ma-2 (Bcl-2) protein, and Bcl-2-associated X protein (Bax). These findings suggest that pectolinarin has the potential to be used as a plant material for functional foods to be applied in the treatment of neurodegenerative diseases, such as Alzheimer's disease, by mitigating oxidative stress-induced damage to neuronal cells.

Ginkgo Biloba and Long COVID: In Vivo and In Vitro Models for the Evaluation of Nanotherapeutic Efficacy

Coronavirus infections are neuroinvasive and can provoke injury to the central nervous system (CNS) and long-term illness consequences. They may be associated with inflammatory processes due to cellular oxidative stress and an imbalanced antioxidant system. The ability of phytochemicals with antioxidant and anti-inflammatory activities, such as Ginkgo biloba, to alleviate neurological complications and brain tissue damage has attracted strong ongoing interest in the neurotherapeutic management of long COVID. Ginkgo biloba leaf extract (EGb) contains several bioactive ingredients, e.g., bilobalide, quercetin, ginkgolides A-C, kaempferol, isorhamnetin, and luteolin. They have various pharmacological and medicinal effects, including memory and cognitive improvement. Ginkgo biloba, through its anti-apoptotic, antioxidant, and anti-inflammatory activities, impacts cognitive function and other illness conditions like those in long COVID. While preclinical research on the antioxidant therapies for neuroprotection has shown promising results, clinical translation remains slow due to several challenges (e.g., low drug bioavailability, limited half-life, instability, restricted delivery to target tissues, and poor antioxidant capacity). This review emphasizes the advantages of nanotherapies using nanoparticle drug delivery approaches to overcome these challenges. Various experimental techniques shed light on the molecular mechanisms underlying the oxidative stress response in the nervous system and help comprehend the pathophysiology of the neurological sequelae of SARS-CoV-2 infection. To develop novel therapeutic agents and drug delivery systems, several methods for mimicking oxidative stress conditions have been used (e.g., lipid peroxidation products, mitochondrial respiratory chain inhibitors, and models of ischemic brain damage). We hypothesize the beneficial effects of EGb in the neurotherapeutic management of long-term COVID-19 symptoms, evaluated using either in vitro cellular or in vivo animal models of oxidative stress.

Mitochondrial dysfunction-targeting therapeutics of natural products in Parkinson's disease

Parkinson's disease (PD), the second most common neurodegenerative disease worldwide, often occurs in middle-aged and elderly individuals. The pathogenesis of PD is complex and includes mitochondrial dysfunction, and oxidative stress. Recently, natural products with multiple structures and their bioactive components have become one of the most important resources for small molecule PD drug research targeting mitochondrial dysfunction. Multiple lines of studies have proven that natural products display ameliorative benefits in PD treatment by regulating mitochondrial dysfunction. Therefore, a comprehensive search of recent published articles between 2012 and 2022 in PubMed, Web of Science, Elesvier, Wliey and Springer was carried out, focusing on original publications related to natural products against PD by restoring mitochondrial dysfunction. This paper presented the mechanisms of various kinds of natural products on PD-related mitochondrial dysfunction regulation and provided evidence that natural products are promising to be developed as drugs for PD therapeutics.

HOTAIRM1 knockdown reduces MPP+-induced oxidative stress injury of SH-SY5Y cells by activating the Nrf2/HO-1 pathway

Objective

Parkinson's disease (PD) is the second most common neurodegenerative disease with complex pathogenesis. Although HOXA transcript antisense RNA myeloid-specific 1 (HOTAIRM1) is upregulated in PD, its exact role in HOTAIRM1 is seldom reported. The purpose of this study is to research the effect of HOTAIRM1 on 1-methyl-4-phenylpyridonium (MPP⁺)-induced cytotoxicity and oxidative stress in SH-SY5Y cells.

Methods

SH-SY5Y cells were treated with MPP⁺ at various concentrations or time points to induce SH-SY5Y cytotoxicity, so as to determine the optimal MPP⁺ concentration and time point. HOTAIRM1 expression upon MPP⁺ treatment was analyzed through qRT-PCR. Next, HOTAIRM1 was downregulated to observe the variance of SH-SY5Y cell viability, apoptosis, oxidative stress-related indexes, and protein levels of the Nrf2/HO-1 pathway. In addition, rescue experiments were carried out to assess the role of Nrf2 silencing in HOTAIRM1 knockdown on MPP⁺-induced oxidative stress in SH-SY5Y cells.

Results

MPP⁺ treatment-induced cytotoxicity and upregulated HOTAIRM1 expression in SH-SY5Y cells in a dose- and time-dependent manner. Mechanically, HOTAIRM1 knockdown enhanced cell viability, limited apoptosis, and oxidative stress, therefore protecting SH-SY5Y cells from MPP⁺-induced SH-SY5Y cytotoxicity. On the other hand, HOTAIRM1 knockdown activated the protein levels of Nrf2 and HO-1. Nrf2 silencing could counteract the neuroprotective effect of HOTAIRM1 knockdown on in vitro PD model.

Conclusion

Our data demonstrated that HOTAIRM1 knockdown could inhibit apoptosis and oxidative stress and activated the Nrf2/HO-1 pathway, therefore exerting neuroprotective effect on the PD cell model.

Neuroprotective effect of hyperoside in MPP+/MPTP -induced dopaminergic neurodegeneration

Parkinson's disease (PD) is a neurodegenerative disease characterized by the pathological loss of nigrostriatal dopaminergic neurons, which causes an insufficient release of dopamine (DA) and then induces motor and nonmotor symptoms. Hyperoside (HYP) is a lignan component with anti-inflammatory, antioxidant, and neuroprotective effects. In this study, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its active neurotoxic metabolite 1-methyl-4-phenylpyridinium ion (MPP⁺) were used to induce dopaminergic neurodegeneration. The results showed that HYP (100 µg/mL) reduced MPTP-mediated cytotoxicity of SH-SY5Y cells in vitro, and HYP [25 mg/(kg d)] alleviated MPTP-induced motor symptoms in vivo. HYP treatment reduced the contents of nitric oxide (NO), H₂O₂, and malondialdehyde (MDA), as well as the mitochondrial damage of dopaminergic neurons, both in vitro and in vivo. Meanwhile, HYP treatment elevated the levels of neurotrophic factors such as glial cell line-derived neurotrophic factor, brain-derived neurotrophic factor, and recombinant cerebral dopamine neurotrophic factor in vivo, but not in vitro. Finally, Akt signaling was activated after the administration of HYP in MPP⁺/MPTP-induced dopaminergic neurodegeneration. However, the blockage of the Akt pathway with Akt inhibitor did not abolish the neuroprotective effect of HYP on DA neurons. These results showed that HYP protected the dopaminergic neurons from the MPP⁺- and MPTP-induced injuries, which did not rely on the Akt pathway.

Estrogenic Activity of 4-Hydroxy-Benzoic Acid from Acer tegmentosum via Estrogen Receptor α-Dependent Signaling Pathways

Acer tegmentosum, a deciduous tree belonging to Aceraceae, has been used in traditional oriental medicine for treating hepatic disorders, such as hepatitis, cirrhosis, and liver cancer. We evaluated the estrogen-like effects of A. tegmentosum using an estrogen receptor (ER)-positive breast cancer cell line, namely MCF-7, to identify potential phytoestrogens and found that an aqueous extract of A. tegmentosum promoted cell proliferation in MCF-7 cells. Five phenolic compounds (1-5) were separated and identified from the active fraction using bioassay-guided fractionation of crude A. tegmentosum extract and phytochemical analysis. The chemical structures of the compounds were characterized as vanillic acid (1), 4-hydroxy-benzoic acid (2), syringic acid (3), isoscopoletin (4), and (E)-ferulic acid (5) based on the analysis of their nuclear magnetic resonance spectra and liquid chromatography-mass spectrometry data. All five compounds were evaluated using an E-screen assay for their estrogen-like effects on MCF-7 cells. Among the tested compounds, only 4-hydroxy-benzoic acid (2) promoted the proliferation of MCF-7 cells, which was mitigated by the ER antagonist, ICI 182,780. The mechanism underlying the estrogen-like effect of 4-hydroxy-benzoic acid (2) was evaluated via western blotting analysis to determine the expression levels of extracellular signal-regulated kinase (ERK), phosphoinositide 3-kinase (PI3K), serine/threonine kinase (AKT), and ERα. Our results demonstrated that 4-hydroxy-benzoic acid (2) induced the increase in the protein expression levels of p-ERK, p-AKT, p-PI3K, and p-Erα, concentration dependently. Collectively, these experimental results suggest that 4-hydroxy-benzoic acid (2) is responsible for the estrogen-like effects of A. tegmentosum and may potentially aid in the control of estrogenic effects during menopause.

Glycolysis: The Next Big Breakthrough in Parkinson's Disease

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the death of dopaminergic neurons. Its pathogenesis comprises defects in the physiological pathway of mitophagy and mutations in the genes involved in this process's regulatory mechanism. PD manifests itself with multiple motor and non-motor symptoms, and currently, there are multiple pharmacological treatments, and unconventional non-drug treatments available. The mainstay of Parkinson's disease treatment has centered around directly manipulating neural mechanisms to retain high dopamine levels, either by exogenous administration, increasing intrinsic production, or inhibiting the breakdown of dopamine. In this review, we highlight a new potential biochemical modality of treatment, treating PD through glycolysis. We highlight how terazosin (TZ), via PGK1, increases ATP levels and how enhanced glycolysis serves a neuroprotective role in PD, and compensates for damage caused by mitophagy. We also discuss the role of quercetin, a bioactive flavonoid, in preventing the development of PD, and reversing mitochondrial dysfunction but only so in diabetic patients. Thus, further research should be conducted on glycolysis as a protective target in PD that can serve to not just prevent, but also alleviate the non-dopaminergic signs and symptoms of PD.

Therapeutic potential of dietary flavonoid hyperoside against non-communicable diseases: targeting underlying properties of diseases

Non-communicable diseases (NCDs) are a global epidemic with diverse pathogenesis. Among them, oxidative stress and inflammation are the most fundamental co-morbid features. Therefore, multi-targets and multi-pathways therapies with significant anti-oxidant and anti-inflammatory activities are potential effective measures for preventing and treating NCDs. The flavonol glycoside compound hyperoside (Hyp) is widely found in a variety of fruits, vegetables, beverages, and medicinal plants and has various health benefits, especially excellent anti-oxidant and anti-inflammatory properties targeting nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-κB (NF-κB) signaling pathways. In this review, we summarize the pathogenesis associated with oxidative stress and inflammation in NCDs and the biological activity and therapeutic potential of Hyp. Our findings reveal that the anti-oxidant and anti-inflammatory activities regulated by Hyp are associated with numerous biological mechanisms, including positive regulation of mitochondrial function, apoptosis, autophagy, and higher-level biological damage activities. Hyp is thought to be beneficial against organ injuries, cancer, depression, diabetes, and osteoporosis, and is a potent anti-NCDs agent. Additionally, the sources, bioavailability, pharmacy, and safety of Hyp have been established, highlighting the potential to develop Hyp into dietary supplements and nutraceuticals.

Targeting Mitochondria as a Therapeutic Approach for Parkinson's Disease

Neurodegeneration is among the most critical challenges that involve modern societies and annually influences millions of patients worldwide. While the pathophysiology of Parkinson's disease (PD) is complicated, the role of mitochondrial is demonstrated. The in vitro and in vivo models and genome-wide association studies in human cases proved that specific genes, including PINK1, Parkin, DJ-1, SNCA, and LRRK2, linked mitochondrial dysfunction with PD. Also, mitochondrial DNA (mtDNA) plays an essential role in the pathophysiology of PD. Targeting mitochondria as a therapeutic approach to inhibit or slow down PD formation and progression seems to be an exciting issue. The current review summarized known mutations associated with both mitochondrial dysfunction and PD. The significance of mtDNA in Parkinson's disease pathogenesis and potential PD therapeutic approaches targeting mitochondrial dysfunction was then discussed.

Therapeutic Potential of Quercetin and its Derivatives in Epilepsy: Evidence from Preclinical Studies

Quercetin is a polyphenolic bioactive compound highly enriched in dietary fruits, vegetables, nuts, and berries. Quercetin and its derivatives like rutin and hyperoside are known for their beneficial effects in various neurological conditions including epilepsy. The clinical studies of quercetin and its derivatives in relation to epilepsy are limited. This review provides the evidence of most recent knowledge of anticonvulsant properties of quercetin and its derivatives on preclinical studies. Additionally, the studies demonstrating antiseizure potential of various plants extracts enriched with quercetin and its derivatives has been included in this review. Herein, we have also discussed neuroprotective effect of these bioactive compound and presented underlying mechanisms responsible for anticonvulsant properties in brief. Finally, limitations of quercetin and its derivatives as antiseizure compounds as well as possible strategies to enhance efficacy have also been discussed.

Evidence for Oxidative Pathways in the Pathogenesis of PD: Are Antioxidants Candidate Drugs to Ameliorate Disease Progression?

Parkinson’s disease (PD) is a progressive neurodegenerative disorder that arises due to a complex and variable interplay between elements including age, genetic, and environmental risk factors that manifest as the loss of dopaminergic neurons. Contemporary treatments for PD do not prevent or reverse the extent of neurodegeneration that is characteristic of this disorder and accordingly, there is a strong need to develop new approaches which address the underlying disease process and provide benefit to patients with this debilitating disorder. Mitochondrial dysfunction, oxidative damage, and inflammation have been implicated as pathophysiological mechanisms underlying the selective loss of dopaminergic neurons seen in PD. However, results of studies aiming to inhibit these pathways have shown variable success, and outcomes from large-scale clinical trials are not available or report varying success for the interventions studied. Overall, the available data suggest that further development and testing of novel therapies are required to identify new potential therapies for combating PD. Herein, this review reports on the most recent development of antioxidant and anti-inflammatory approaches that have shown positive benefit in cell and animal models of disease with a focus on supplementation with natural product therapies and selected synthetic drugs.

[Hyperoside protects mouse spermatocytes GC-2 cells from oxidative damage by activating the Keap1/Nrf2/HO-1 pathway]

OBJECTIVE

To study the protective effect of hyperoside (Hyp) against ydrogen peroxide (H2O2)- induced oxidative damage in mouse spermatocytes GC-2 cells and explore the role of the Keap1/Nrf2/HO-1 pathway in this protective mechanism.

METHODS

GC-2 cells were treated with 2.5 mmol/L azaacetylcysteine (NAC), 50, 100, and 200 μmol/L hyperoside, or the culture medium for 48 h before exposure to H2O2 (150 μmol/L) for 2 h. CCK-8 assay was used to detect the changes in cell viability, and cell apoptosis was analyzed using flow cytometry. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), catalase (CAT) activity and malondialdehyde (MDA) in the culture medium. Western blotting and RT-qPCR were used to detect the protein and mRNA expression levels of nuclear factor erythroid 2-related factor2 (Nrf2), Kelch-like ECH-associated protein 1 (Keap1), and heme oxygenase-1 (HO-1); the nuclear translocation of Nrf2 was detected using immunofluorescence assay.

RESULTS

Exposure to H2O2 significantly lowered the proliferation rate, reduced the activities of SOD, GSH and CAT, and obviously increased MDA content, cell apoptosis rate, and the expressions of Keap1 and Nrf2 mRNA and Keap1 protein in GC-2 cells (P < 0.05 or 0.01). Treatment of the cells prior to H2O2 exposure with either NAC or 200 μmol/L hyperoside significantly increased the cell proliferation rate, enhanced the activities of SOD, GSH-PX and CAT, and lowered MDA content and cell apoptosis rate (P < 0.05). Treatment with 200 μmol/L hyperoside significantly decreased the mRNA and protein expressions of Keap1 and increased the expressions of HO-1 mRNA and the protein expressions of Nrf2 and HO-1 (P < 0.05 or 0.01). Hyperoside also caused obvious nuclear translocation of Nrf2 in the cells (P < 0.05).

CONCLUSION

Hyperoside protects GC-2 cells against H2O2- induced oxidative damage possibly by activation of the Keap1/Nrf2/HO-1 signaling pathway.

Hyperoside: A review on its sources, biological activities, and molecular mechanisms

Hyperoside is a natural flavonol glycoside in various plants, such as Crataegus pinnatifida Bge, Forsythia suspensa, and Cuscuta chinensis Lam. Medical research has found that hyperoside possesses a broad spectrum of biological activities, including anticancer, anti-inflammatory, antibacterial, antiviral, antidepressant, and organ protective effects. These pharmacological properties lay the foundation for its use in treating multiple diseases, such as sepsis, arthritis, colitis, diabetic nephropathy, myocardial ischemia-reperfusion, pulmonary fibrosis, and cancers. Hyperoside is obtained from the plants and chemical synthesis. This study aims to provide a comprehensive overview of hyperoside on its sources and biological activities to provide insights into its therapeutic potential, and to provide a basis for high-quality studies to determine the clinical efficacy of this compound.

Hyperoside: A Review of Its Structure, Synthesis, Pharmacology, Pharmacokinetics and Toxicity

Hyperoside is an active ingredient in plants, such as Hypericum monogynum in Hypericaceae, Crataegus pinnatifida in Rosaceae and Polygonum aviculare in Polygonaceae. Its pharmacologic effects include preventing cancer and protecting the brain, neurons, heart, kidneys, lung, blood vessels, bones, joints and liver, among others. Pharmacokinetic analysis of hyperoside has revealed that it mainly accumulates in the kidney. However, long-term application of high-dose hyperoside should be avoided in clinical practice because of its renal toxicity. This review summarises the structure, synthesis, pharmacology, pharmacokinetics and toxicity of hyperoside.

The potential applications of traditional Chinese medicine in Parkinson's disease: A new opportunity

Parkinson's disease (PD) presents a common challenge for people all over the world and has become a major research hotspot due to the large population affected by the illness and the difficulty of clinical treatment. The prevalence of PD is increasing every year, the pathogenesis is complex, and the current treatment is ineffective. Therefore, it has become imperative to find effective drugs for PD. With the advantages of low cost, high safety and high biological activity, Chinese medicine has great advantages in the prevention and treatment of PD. This review systematically summarizes the potential of Chinese medicine for the treatment of PD, showing that Chinese medicine can exert anti-PD effects through various pathways, such as anti-inflammatory and antioxidant pathways, reducing mitochondrial dysfunction, inhibiting endoplasmic reticulum stress and iron death, and regulating intestinal flora. These mainly involve HMGB1/TLR4, PI3K/Akt, NLRP3/ caspase-1/IL-1β, Nrf2/HO-1, SIRT1/Akt1, PINK1/parkin, Bcl-2/Bax, BDNF-TrkB and other signaling pathways. In sum, based on modern phytochemistry, pharmacology and genomic proteomics, Chinese medicine is likely to be a potential candidate for PD treatment, which requires more clinical trials to further elucidate its importance in the treatment of PD.

Preparation and Properties of Cyclodextrin Inclusion Complexes of Hyperoside

In order to improve the aqueous solubility and enhance the bioavailability of Hyperoside (Hyp), three inclusion complexes (ICs) of Hyp with 2-hydroxypropyl-β-cyclodextrin (2H-β-CD), β-cyclodextrin (β-CD), and methyl-β-cyclodextrin (M-β-CD) were prepared using the ultrasonic method. The characterization of the inclusion complexes (ICs) was achieved using Fourier-transform infrared spectroscopy (FTIR), scanning electronic microscopy (SEM), X-ray powder diffraction (XRPD), thin-layer chromatography (TLC), and ¹H nuclear magnetic resonance (¹H NMR). The effects of the ICs on the solubility and antioxidant activity of Hyp were investigated. A Job’s plot revealed that the Hyp formed ICs with three kinds of cyclodextrin (CD), all at a 1:1 stoichiometric ratio. The FTIR, SEM, XRPD, TLC, and ¹H NMR results confirmed the formation of inclusion complexes. The water solubility of the IC of Hyp with 2-hydroxypropyl-β-cyclodextrin was enhanced 9-fold compared to the solubility of the original Hyp. The antioxidant activity tests showed that the inclusion complexes had higher antioxidant activities compared to free Hyp in vitro and the H₂O₂–RAW264.7 cell model. Therefore, encapsulation with CDs can not only improve Hyp’s water solubility but can also enhance its biological activity, which provides useful information for the potential application of complexation with Hyp in a clinical context.

Antidepressant Potential of Quercetin and its Glycoside Derivatives: A Comprehensive Review and Update

Depression is a global health problem with growing prevalence rates and serious impacts on the daily life of patients. However, the side effects of currently used antidepressants greatly reduce the compliance of patients. Quercetin is a flavonol present in fruits, vegetables, and Traditional Chinese medicine (TCM) that has been proved to have various pharmacological effects such as anti-depressant, anti-cancer, antibacterial, antioxidant, anti-inflammatory, and neuroprotective. This review summarizes the evidence for the pharmacological application of quercetin to treat depression. We clarified the mechanisms of quercetin regulating the levels of neurotransmitters, promoting the regeneration of hippocampal neurons, improving hypothalamic-pituitary-adrenal (HPA) axis dysfunction, and reducing inflammatory states and anti-oxidative stress. We also summarized the antidepressant effects of some quercetin glycoside derivatives to provide a reference for further research and clinical application.

A new arsenal of polyphenols to make Parkinson's disease extinct: HPLC-MS/MS profiling, very interesting MAO-B inhibitory activity and antioxidant activity of Otostegia fruticosa

Fifteen compounds belong to phenolic acids, derivatives of phenolic acids, iridoids, xanthones and flavonoids were characterized in the methanolic extract of Otostegia fruticosa leaves using HPLC-MS/MS. Extract has been also investigated for its MAO-B inhibitory activity, antioxidant activity, total phenolic and total flavonoid content. The extract exhibited interesting MAO-B inhibitory activity (IC50; 2.24 ± 0.08) compared to the reference compound selegiline (0.55 ± 0.02 µg/mL). It also showed a potent antioxidant activity proven in both DPPH and ORAC assay methods. The extract showed an IC50 of 3.64 ± 1.22 µg/mL in the DPPH test which was significantly lower than that of the standard ascorbic acid which attained an IC50 of 18.3 ± 1.41 µg/mL. Moreover, in the oxygen radical absorbance capacity assay (ORAC) the extract showed a decline in the IC50 to 3.48 ± 1.16 µg/mL as compared to the standard Trolox which exhibited an IC50 of 27.0 ± 13.41.

Neuroprotective evaluation of novel substituted 1,3,4-oxadiazole and aroylhydrazone derivatives

The paper reports on the facile and convenient synthesis of a series of novel 2,5-substituted 1,3,4-oxadiazoles 3a-f and that of aroylhydrazone-based molecular hybrids 5a-g from readily available starting materials. The structure of the compounds was confirmed by IR, ¹H-NMR, ¹³C-NMR and HRESI-MS spectral data. The toxicological potential of the compounds was evaluated by monitoring the synaptosomal viability and the levels of reduced glutathione in rat brain synaptosomes, isolated by Percoll gradient. The neuroprotective effects were assessed in vitro in a model of 6-hydroxydopamine-induced neurotoxicity. Administered alone, at a concentration of 40 µM, most of the 1,3,4-oxadiazole derivatives and all of the hydrazone derivatives exhibited weak statistically significant neurotoxic effects, compared to the control. Two of the compounds from the novel oxadiazoles 3a and 3d did not have any toxicity. In a model of 6-OHDA-induced oxidative stress, again 3a and 3d and all aroylhydrazone derivatives 5a-g revealed statistically significant neuroprotective effect by preserving the synaptosomal viability and the level of reduced glutathione, against the toxic agent. Some of the compounds may have neuroprotective effects due to possible stabilization of the synaptosomal membrane and/or because of the preserved reduced glutathione. Additionally, all the compounds display a good predicted ADME profile.

Pharmacological Modulation of Nrf2/HO-1 Signaling Pathway as a Therapeutic Target of Parkinson's Disease

Parkinson’s disease (PD) is a complex neurodegenerative disorder featuring both motor and nonmotor symptoms associated with a progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Oxidative stress (OS) has been implicated in the pathogenesis of PD. Genetic and environmental factors can produce OS, which has been implicated as a core contributor to the initiation and progression of PD through the degeneration of dopaminergic neurons. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) orchestrates activation of multiple protective genes, including heme oxygenase-1 (HO-1), which protects cells from OS. Nrf2 has also been shown to exert anti-inflammatory effects and modulate both mitochondrial function and biogenesis. Recently, a series of studies have reported that different bioactive compounds were shown to be able to activate Nrf2/antioxidant response element (ARE) and can ameliorate PD-associated neurotoxin, both in animal models and in tissue culture. In this review, we briefly overview the sources of OS and the association between OS and the pathogenesis of PD. Then, we provided a concise overview of Nrf2/ARE pathway and delineated the role played by activation of Nrf2/HO-1 in PD. At last, we expand our discussion to the neuroprotective effects of pharmacological modulation of Nrf2/HO-1 by bioactive compounds and the potential application of Nrf2 activators for the treatment of PD. This review suggests that pharmacological modulation of Nrf2/HO-1 signaling pathway by bioactive compounds is a therapeutic target of PD.

Hyperoside Reduces Rotenone-induced Neuronal Injury by Suppressing Autophagy

Hyperoside has a variety of pharmacological activities, including anti-liver injury, anti-depression, anti-inflammatory, and anti-cancer activities. However, the effect of hyperoside on Parkinson's disease (PD) is still unclear. Therefore, we tried to study the therapeutic effect and mechanism of hyperoside on PD in vivo and in vitro models. Rotenone was used to induce PD rat model and SH-SY5Y cell injury model, and hyperoside was used for intervention. Immunohistochemistry, animal behavior assays, TUNEL and Western blot were constructed to observe the protective effect and related mechanisms of hyperoside in vivo. Cell counting kit-8 (CCK-8), flow cytometry, Rh123 staining and Western blot were used for in vitro assays. Rapamycin (RAP) pretreatment was used in rescue experiments to verify the relationship between hyperoside and autophagy in rotenone-induced SH-SY5Y cells. Hyperoside promoted the number of tyrosine hydroxylase (TH)-positive cells, improved the behavioral defects of rats, and inhibited cell apoptosis in vivo. Different concentrations of hyperoside had no significant effect on SH-SY5Y cell viability, but dramatically reversed the rotenone-induced decrease in cell viability, increased apoptosis and loss of cell mitochondrial membrane potential in vitro. Additionally, hyperoside reversed the regulation of rotenone on the Beclin1, LC3II, Bax, cleaved caspase 3, Cyc and Bcl-2 expressions in rat SNpc tissues and SH-SY5Y cells, while promoted the regulation of rotenone on the P62 and α-synuclcin. Furthermore, RAP reversed the effect of hyperoside on rotenone-induced SH-SY5Y cells. Hyperoside may play a neuroprotective effect in rotenone-induced PD rat model and SH-SY5Y cell model by affecting autophagy.

Activation of Nrf2 in Astrocytes Suppressed PD-Like Phenotypes via Antioxidant and Autophagy Pathways in Rat and Drosophila Models

The oxidative-stress-induced impairment of autophagy plays a critical role in the pathogenesis of Parkinson's disease (PD). In this study, we investigated whether the alteration of Nrf2 in astrocytes protected against 6-OHDA (6-hydroxydopamine)- and rotenone-induced PD-like phenotypes, using 6-OHDA-induced rat PD and rotenone-induced Drosophila PD models. In the PD rat model, we found that Nrf2 expression was significantly higher in astrocytes than in neurons. CDDO-Me (CDDO methyl ester, an Nrf2 inducer) administration attenuated PD-like neurodegeneration mainly through Nrf2 activation in astrocytes by activating the antioxidant signaling pathway and enhancing autophagy in the substantia nigra and striatum. In the PD Drosophila model, the overexpression of Nrf2 in glial cells displayed more protective effects than such overexpression in neurons. Increased Nrf2 expression in glial cells significantly reduced oxidative stress and enhanced autophagy in the brain tissue. The administration of the Nrf2 inhibitor ML385 reduced the neuroprotective effect of Nrf2 through the inhibition of the antioxidant signaling pathway and autophagy pathway. The autophagy inhibitor 3-MA partially reduced the neuroprotective effect of Nrf2 through the inhibition of the autophagy pathway, but not the antioxidant signaling pathway. Moreover, Nrf2 knockdown caused neurodegeneration in flies. Treatment with CDDO-Me attenuated the Nrf2-knockdown-induced degeneration in the flies through the activation of the antioxidant signaling pathway and increased autophagy. An autophagy inducer, rapamycin, partially rescued the neurodegeneration in Nrf2-knockdown Drosophila by enhancing autophagy. Our results indicate that the activation of the Nrf2-linked signaling pathways in glial cells plays an important neuroprotective role in PD models. Our findings not only provide a novel insight into the mechanisms of Nrf2-antioxidant-autophagy signaling, but also provide potential targets for PD interventions.

Quercetin: A Bioactive Compound Imparting Cardiovascular and Neuroprotective Benefits: Scope for Exploring Fresh Produce, Their Wastes, and By-Products

Quercetin, a bioactive secondary metabolite, holds incredible importance in terms of bioactivities, which has been proved by in vivo and in vitro studies. The treatment of cardiovascular and neurological diseases by quercetin has been extensively investigated over the past decade. Quercetin is present naturally in appreciable amounts in fresh produce (fruits and vegetables). However, today, corresponding to the growing population and global demand for fresh fruits and vegetables, a paradigm shift and focus is laid towards exploring industrial food wastes and/or byproducts as a new resource to obtain bioactive compounds such as quercetin. Based on the available research reports over the last decade, quercetin has been suggested as a reliable therapeutic candidate for either treating or alleviating health issues, mainly those of cardiovascular and neurological diseases. In the present review, we have summarized some of the critical findings and hypotheses of quercetin from the available databases foreseeing its future use as a potential therapeutic agent to treat cardiovascular and neurological diseases. It is anticipated that this review will be a potential reference material for future research activities to be undertaken on quercetin obtained from fresh produce as well as their respective processing wastes/byproducts that rely on the circular concept.

Campanula macrostachya: biological activity and identification of phenolics using a liquid chromatography electrospray ionization tandem mass spectrometry system

It is known that some Campanula species are traditionally used because of their anti-allergic, spasmolytic, antiphlogistic, antioxidant, and antiviral properties. This study was designed to evaluate the phytochemical composition, antioxidant, α-amylase, and tyrosinase inhibitory activity of ethyl acetate, methanol, and water extracts of Campanula macrostachya Waldst. & Kit. ex Willd. Chemical compositions were analyzed by spectrophotometric and chromatographic methods. Antioxidant activities of the samples were tested by using five different test systems. Enzyme inhibitory activities of the extracts were also studied. As a result of the LC-ESI-MS/MS analyses, chlorogenic acid, hesperidin, and hyperoside were found to be the major compounds of the extracts, especially the MeOH extract (6559.59, 2499.22, and 2047.66 μg/g extract, respectively). Antioxidant activity tests have proven that MeOH extract showed higher activity than others (DPPH: 4.15 mg/mL, ABTS: 2.05 mg/mL, CUPRAC: 1.80 mg/mL, FRAP: 0.83 mg/mL, phosphomolybdenum: 1.69 mg/mL). Ferrous ion chelating activity of the water extract was 1.03 mg/mL. In α-amylase and tyrosinase inhibitory assays, EtOAc (IC₅₀: 2.54 mg/mL) and MeOH (IC₅₀: 1.51 mg/mL) extracts showed higher activity than the others did. In phosphomolybdenum, CUPRAC, FRAP, and tyrosinase inhibitory assays, the activity was strongly correlated with flavonoids, chlorogenic acid, hesperidin, and hyperoside. On the other hand, phenolic compounds have been found to contribute more to radical scavenging activity. Pearson correlation analysis showed that phenolics and flavonoids were not responsible for the α-amylase inhibitory activity of EtOAc extract.

Administration of quercetin improves mitochondria quality control and protects the neurons in 6-OHDA-lesioned Parkinson's disease models

Mounting evidence suggests that mitochondrial dysfunction and impaired mitophagy lead to Parkinson’s disease (PD). Quercetin, one of the most abundant polyphenolic flavonoids, displays many health-promoting biological effects in many diseases. We explored the neuroprotective effect of quercetin in vivo in the 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD and in vitro in 6-OHDA-treated PC12 cells. In vitro, we found that quercetin (20 μM) treatment improved mitochondrial quality control, reduced oxidative stress, increased the levels of the mitophagy markers PINK1 and Parkin and decreased α-synuclein protein expression in 6-OHDA-treated PC12 cells. Moreover, our in vivo findings demonstrated that administration of quercetin also relieved 6-OHDA-induced progressive PD-like motor behaviors, mitigated neuronal death and reduced mitochondrial damage and α-synuclein accumulation in PD rats. Furthermore, the neuroprotective effect of quercetin was suppressed by knockdown of either Pink1 or Parkin.

Hyperoside protects cardiomyocytes against hypoxia‑induced injury via upregulation of microRNA‑138

Following hypoxia, cardiomyocytes are susceptible to damage, against which microRNA (miR)‑138 may act protectively. Hyperoside (Hyp) is a Chinese herbal medicine with multiple biological functions that serve an important role in cardiovascular disease. The aim of the present study was to investigate the role of Hyp in hypoxic cardiomyocytes and its effect on miR‑138. A hypoxia model was established in both H9C2 cells and C57BL/6 mice, which were stimulated by Hyp. The expression levels of miR‑138 were increased in the hypoxic myocardium in the presence of Hyp at concentrations of >50 µmol/l in vivo and >50 mg/kg in vitro. Using Cell Counting Kit‑8 and 5‑ethynyl‑2'‑deoxyuridine assays, it was observed that Hyp improved hypoxia‑induced impairment of cell proliferation. Cell apoptosis was evaluated by flow cytometry and a TUNEL assay. The number of apoptotic cells in the Hyp group was lower than that in the control group. As markers of myocardial injury, the levels of lactate dehydrogenase, creatine kinase‑myocardial band isoenzyme and malondialdehyde were decreased in the Hyp group compared with the control group, whereas the levels of superoxide dismutase were increased. A marked decrease in the levels of cleaved caspase‑3 and cleaved poly(ADP) ribose polymerase and a marked increase in expression levels of Bcl‑2 were observed in the presence of Hyp. However, miR‑138 inhibition by antagomir attenuated the protective effects of Hyp. Furthermore, Hyp treatment was associated with marked downregulation of mixed lineage kinase 3 and lipocalin‑2, but not pyruvate dehydrogenase kinase 1, in hypoxic H9C2 cells. These findings demonstrated that Hyp may be beneficial for myocardial cell survival and may alleviate hypoxic injury via upregulation of miR‑138, thereby representing a promising potential strategy for clinical cardioprotection.

Hyperoside attenuates neuroinflammation, cognitive impairment and oxidative stress via suppressing TNF-α/NF-κB/caspase-3 signaling in type 2 diabetes rats

OBJECTIVES

Literature findings have instituted the role of hyperglycemia-induced oxidative stress and inflammation in the pathogenesis of cognitive derangement in diabetes mellitus (DM). Hyperoside (HYP) is a flavanone glycoside reported to possess diverse pharmacological benefits such as antioxidant and anti-inflammatory properties. The study explored whether HYP could mitigate DM-induced cognitive dysfunction and further elucidate on potential molecular mechanism in rats.

METHODS

Streptozotocin/high-fat diet-induced diabetic rats were treated orally with HYP (50, 200 and 400 mg/kg/day) for six consecutive weeks. The blood glucose and serum insulin levels, Morris water maze test, intraperitoneal glucose tolerance test, and brain acetylcholinesterase (AChE) activity were determined. The brain expression of inflammatory nuclear factor-kappa B (NF-κB), tumour necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), as well as superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), total antioxidant capacity (TAC), malondialdehyde (MDA), lipid profile and caspase-3 activity were estimated.

RESULTS

DM evoked hyperlipidemia, hypoinsulinemia, cognitive dysfunction by markedly increased AChE and reduction in learning and memory capacity. Brain activities of SOD and CAT, and levels of TAC and GSH were considerably depressed, whereas levels of IL-1β, IL-6, TNF-α, NF-κB, caspase-3 and MDA were prominently increased. Interestingly, the HYP treatment dose-dependently abrogated the altered cognitive and biochemical parameters.

DISCUSSION

The results suggested that hyperoside prevents DM-induced cognitive dysfunction, neuroinflammation and oxidative stress via antioxidant, anti-inflammatory and antiapoptotic mechanisms in rats.

Potential therapeutic effects of polyphenols in Parkinson's disease: in vivo and in vitro pre-clinical studies

Parkinson’s disease is a neurodegenerative disorder characterized by a combination of severe motor and non-motor symptoms. Over the years, several factors have been discovered to play a role in the pathogenesis of this disease, in particular, neuroinflammation and oxidative stress. To date, the pharmacological treatments used in Parkinson’s disease are exclusively symptomatic. For this reason, in recent years, the research has been directed towards the discovery and study of new natural molecules to develop potential neuroprotective therapies against Parkinson’s disease. In this context, natural polyphenols have raised much attention for their important anti-inflammatory and antioxidant properties, but also for their ability to modulate protein misfolding. In this review, we propose to summarize the relevant in vivo and in vitro studies concerning the potential therapeutic role of natural polyphenols in Parkinson’s disease.

High KEAP1, NRF2 and Low HO-1 Serum Levels in Children with Autism

Introduction

The purpose of our study was to investigate heme oxygenase-1 (HO-1), nuclear factor erythroid-2-related factor 2 (NRF2), and kelch-like ECH-associated protein 1 (KEAP1) levels in children with autism spectrum disorder (ASD) and to reveal their association with the severity of autism.

Methods

This study measured serum HO-1, KEAP1, and NRF2 levels in 43 patients with ASD (aged 3-12 years) and in 41 age- and gender-matched healthy controls. ASD severity was rated using the Childhood Autism Rating Scale (CARS). HO-1, KEAP1, and NRF2 levels were determined in the biochemistry laboratory using the ELISA technique.

Results

HO-1 levels were significantly lower in patients aged 3-12 years compared to controls aged 3-12, while KEAP1 and NRF2 levels were significantly higher (p=0.020, p<0.001, and p=0.017, respectively). No correlation was determined between ASD severity on the basis of total CARS scores and HO-1, KEAP1 or NRF2 (p>0.05).

Conclusion

This study suggests that oxidative stress is higher in children with ASD and that HO-1 levels are insufficient to achieve oxidative balance.

Isoorientin exerts a protective effect against 6-OHDA-induced neurotoxicity by activating the AMPK/AKT/Nrf2 signalling pathway

Parkinson's disease (PD) is a progressive neurodegenerative disorder that is closely associated with oxidative stress. Nuclear factor erythroid 2 related factor 2 (Nrf2) is a key transcription factor that regulates oxidative stress. Isoorientin (IOT), as a dietary C-glucosyl flavone derived from rooibos tea, cereals and legumes, is thought to possess multiple pharmacological activities; however, the protective effect of IOT against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in SH-SY5Y cells is still poorly understood. The present study focused on investigating whether IOT could ameliorate neurotoxicity and the underlying mechanisms. Our findings indicated that IOT significantly inhibited neurotoxicity reduced apoptotic cell numbers, reactive oxygen species (ROS) overproduction and mitochondrial membrane potential, and modulated the expression of apoptosis-related proteins, including Bcl-2, Bax and caspase-3, which were induced by 6-OHDA. Moreover, IOT also enhanced the expression of the GCLC, GCLM, HO-1, NQO1 and Trx-1 proteins, which mostly depends on the nuclear translation of Nrf2 and reduced expression of the Keap1 protein. IOT significantly increased the phosphorylation of AMPK, ERK, GSK3β, JNK, PI3K and AKT. In contrast, pretreatment with the inhibitors of AMPK and PI3K/AKT only suppressed the nuclear translocation of Nrf2. In addition, the expression of these proteins was effectively decreased by 6-OHDA, and this effect was reversed by IOT treatment. Importantly, the effect of IOT on improving 6-OHDA induced neurotoxicity was remarkably abrogated by the application of Nrf2 siRNA and, AMPK and PI3K/AKT inhibitors. In summary, IOT might play a protective role against 6-OHDA-induced neurotoxicity by inducing the expression of various antioxidant enzymes via the activation of the AMPK/AKT-Nrf2 signalling pathway.

Hyperoside alleviates epilepsy-induced neuronal damage by enhancing antioxidant levels and reducing autophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Hypericum perforatum L. (genus Hypericum, family Hypericaceae), a plant commonly used in traditional Chinese medicine, is believed to confer a wide range of benefits, including fever reduction, detoxification, calming, and pain relief via decoctions of its stems and leaves. Hyperoside (HYP), a natural compound extracted from Hypericum perforatum L., has been shown to demonstrate a wide array of bioactivities including antioxidative, anti-inflammatory, and anti-apoptotic effects. In this study, we investigated the effects of HYP on epilepsy-induced neuronal damage in mice and the associated regulatory factors.

AIM OF THE STUDY

This study examined the potential therapeutic use of HYP for the treatment of neuronal damage in a mouse model of epilepsy and explored the relationships of the potential neuroprotective effects of HYP pretreatment with antioxidant levels and autophagy.

MATERIALS AND METHODS

ICR mice were randomly divided into six groups: sham group, sham-HYP group, KA group, KA-HYP group, KA-HYP-DDC group and KA-CQ group. Immunohistochemical staining was used to assess changes in NeuN, IBA-1, and GFAP expression in the CA3 region of the hippocampus. Immunofluorescence staining was used to assess the effects of HYP on the number of autophagosomes that accumulated in neurons in the hippocampal CA3 region. The levels of SOD1, SOD2, LC3I/II, Beclin1, and PI3K/AKT and MAPK signaling-related proteins were detected by Western blot.

RESULTS

Pretreatment with 50 mg/kg HYP protected against epilepsy-induced neuronal damage in the hippocampal CA3 region. Additionally, HYP enhanced antioxidant levels and reduced the levels of autophagy-related proteins via the PI3K/AKT and MAPK pathways.

CONCLUSION

HYP protected the hippocampal CA3 region against epilepsy-induced neuronal damage via enhancing antioxidant levels and reducing autophagy. The mechanism of action may be related to the maintenance of antioxidant levels and the suppression of autophagy via the PI3K/Akt and MAPK pathways.

Hyperoside attenuates pregnancy loss through activating autophagy and suppressing inflammation in a rat model

AIMS

Recurrent pregnancy loss (RPL) is one of the most common obstetrical diseases, which is a manifestation of antiphospholipid syndrome (APS) with no effective therapy methods. Autophagy and inflammatory responses both play an important role in the pathogenesis of RPL and hyperoside has been demonstrated to have multifarious bioactivities including enhancing autophagy and anti-inflammation. This study aims to investigate the effect of hyperoside on anticardiolipin (aCL)-IgG fractions-induced pregnancy loss.

MAIN METHODS

In the present study, the effect of hyperoside was evaluated in a rat model of pregnancy loss induced by aCL-IgG fractions isolated from serum of APS patients. The fetuses were counted and the placentas were weighted and the protein expressions of inflammation and autophagy were measured by western blot analysis.

KEY FINDINGS

Treatment with hyperoside (40 mg/kg) improved pregnancy outcome manifest as increasing the weight of fetuses and decreasing the fetal resorption rate. In addition, hyperoside treatment downregulated the expressions of phosphorylated mammalian target of rapamycin (mTOR), phosphorylated p70S6 Kinase (S6K) and inhibited the expressions of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and NF-kB p-p65 in pregnancy loss animal models.

SIGNIFICANCE

Hyperoside attenuated pregnancy loss through regulating mTOR/S6K and TLR4/MyD88/NF-kB signaling pathways, which may provide a potential drug candidate for recurrent pregnancy loss therapy.

Human Heme Oxygenase-1 Induced by Interleukin-6 via JAK/STAT3 Pathways Is a Tumor Suppressor Gene in Hepatoma Cells

Heme oxygenase-1 (HO-1) has several important roles in hepatocytes in terms of anti-inflammation, anti-apoptosis, and antioxidant properties. Interleukin-6 (IL-6) is a pleiotropic cytokine associated with liver regeneration and protection against injury. The aim of this study was to determine the potential crosstalk between HO-1 and IL-6, and to elucidate the signaling pathways involved in the induction of HO-1 by IL-6 in human hepatoma cells. Ectopic overexpression of HO-1 not only attenuated cell proliferation in vitro and in vivo, but also blocked the reactive oxygen species (ROS) induced by H₂O₂ and the pyocyanin in HepG2 or Hep3B cells. IL-6 expression was negatively regulated by HO-1, while IL-6 induced signal transducer and activator of transcription 3 (STAT3) phosphorylation and HO-1 gene expression in HepG2 cells. The co-transfected HO-1 reporter vector and a protein inhibitor of the activated STAT3 (PIAS3) expression vector blocked the IL-6-induced HO-1 reporter activity. Both interferon γ and interleukin-1β treatments induced STAT1 but not STAT3 phosphorylation, which had no effects on the HO-1 expression. Treatments of AG490 and luteolin blocked the JAK/STAT3 signaling pathways which attenuated IL-6 activation on the HO-1 expression. Our results indicated that HO-1 is the antitumor gene induced by IL-6 through the IL-6/JAK/STAT3 pathways; moreover, a feedback circuit may exist between IL-6 and HO-1 in hepatoma cells.