The Nrf2/HO-1 Axis as Targets for Flavanones: Neuroprotection by Pinocembrin, Naringenin, and Eriodictyol

Neuroprotective effect of curcumin against experimental autoimmune encephalomyelitis-induced cognitive and physical impairments in mice: an insight into the role of the AMPK/SIRT1 pathway

Multiple sclerosis (MS) is an incurable chronic neurodegenerative disease where autoimmunity, oxidative stress, and neuroinflammation collaboration predispose myelin sheath destruction. Interestingly, curcumin, a natural polyphenol, showed a neuroprotective effect in numerous neurodegenerative diseases, including MS. Nevertheless, the influence of curcumin against MS-induced cognitive impairment is still vague. Hence, we induced experimental autoimmune encephalomyelitis (EAE) in mice using spinal cord homogenate (SCH) and complete Freund's adjuvant, which eventually mimic MS. This study aimed not only to evaluate curcumin efficacy against EAE-induced cognitive and motor dysfunction, but also to explore a novel mechanism of action, by which curcumin exerts its beneficial effects in MS. Curcumin (200 mg/kg/day) efficacy was evaluated by behavioral tests, histopathological examination, and biochemical tests. Concisely, curcumin amended EAE-induced cognitive and motor impairments, as demonstrated by the behavioral tests and histopathological examination of the hippocampus. Interestingly, curcumin activated the adenosine monophosphate (AMP)-activated protein kinase/silent mating type information regulation 2 homolog 1 (AMPK/SIRT1) axis, which triggered cyclic AMP response element-binding protein/brain-derived neurotrophic factor/myelin basic protein (CREB/BDNF/MBP) pathway, hindering demyelination of the corpus callosum. Furthermore, AMPK/SIRT1 activation augmented nuclear factor erythroid 2-related factor 2 (Nrf2), a powerful antioxidant, amending EAE-induced oxidative stress. Additionally, curcumin abolished EAE-induced neuroinflammation by inhibiting Janus kinase 2 /signal transducers and activators of transcription 3 (JAK2/STAT3) axis, by various pathways, including AMPK/SIRT1 activation. JAK2/STAT3 inhibition halts inflammatory cytokines synthesis. In conclusion, curcumin's neuroprotective effect in EAE is controlled, at least in part, by AMPK/SIRT1 activation, which ultimately minimizes EAE-induced neuronal demyelination, oxidative stress, and neuroinflammation.

Long term exercise-derived exosomal LncRNA CRNDE mitigates myocardial infarction injury through miR-489-3p/Nrf2 signaling axis

Myocardial infarction (MI) is a cardiovascular disease and troubles patients all over the world. Exosomes produced after long-term exercise training were discovered to mediate intercellular communication and alleviate MI-induced heart injury. However, the detailed roles of long-term exercise-derived exosomal long noncoding RNAs (LncRNAs) in MI remain uncovered. In this study, we collected and identified long-term exercise-derived exosomes, and established MI or hypoxia/reoxygenation (H/R) model after LncRNA colorectal neoplasia differentially expressed (CRNDE) depletion. This work proved that LncRNA CRNDE was highly expressed in long-term exercise-derived exosomes (p = 0.0078). CRNDE knockdown increased cardiomyocytes apoptosis and oxidative stress (p = 0.0036), and suppressed MI progress (p = 0.0005). CRNDE served as the sponge of miR-489-3p to affect Nrf2 expression (p = 0.0001). MiR-489-3p inhibition effectively reversed the effects of CRNDE depletion on hypoxia cardiomyocytes (p = 0.0002). These findings offered a promising therapeutic option for the treatment of MI.

Unleashing the Potential of Nrf2: A Novel Therapeutic Target for Pulmonary Vascular Remodeling

Pulmonary vascular remodeling, characterized by the thickening of all three layers of the blood vessel wall, plays a central role in the pathogenesis of pulmonary hypertension (PH). Despite the approval of several drugs for PH treatment, their long-term therapeutic effect remains unsatisfactory, as they mainly focus on vasodilation rather than addressing vascular remodeling. Therefore, there is an urgent need for novel therapeutic targets in the treatment of PH. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a vital transcription factor that regulates endogenous antioxidant defense and emerges as a novel regulator of pulmonary vascular remodeling. Growing evidence has suggested an involvement of Nrf2 and its downstream transcriptional target in the process of pulmonary vascular remodeling. Pharmacologically targeting Nrf2 has demonstrated beneficial effects in various diseases, and several Nrf2 inducers are currently undergoing clinical trials. However, the exact potential and mechanism of Nrf2 as a therapeutic target in PH remain unknown. Thus, this review article aims to comprehensively explore the role and mechanism of Nrf2 in pulmonary vascular remodeling associated with PH. Additionally, we provide a summary of Nrf2 inducers that have shown therapeutic potential in addressing the underlying vascular remodeling processes in PH. Although Nrf2-related therapies hold great promise, further research is necessary before their clinical implementation can be fully realized.

Cryopreservation of bioflavonoid-rich plant sources and bioflavonoid-microcapsules: emerging technologies for preserving bioactivity and enhancing nutraceutical applications

Bioflavonoids are natural polyphenolic secondary metabolites that are medicinal. These compounds possess antitumor, cardioprotective, anti-inflammatory, antimicrobial, antiviral, and anti-psoriasis properties to mention a few. Plant species that contain bioflavonoids should be preserved as such. Also, the bioactivity of the bioflavonoids as neutraceutical compounds is compromised following extraction due to their sensitivity to environmental factors like light, pH, and temperature. In other words, the bioflavonoids' shelf-life is affected. Scientists noticed that bioflavonoids have low solubility properties, poor absorption, and low bioavailability following consumption. Researchers came up with methods to encapsulate bioflavonoids in order to circumvent the challenges above and also to mask the unpleasant order these chemicals may have. Besides, scientists cryopreserve plant species that contain bioflavonoids. In this review, we discuss cryopreservation and bioflavonoid microencapsulation focusing mainly on vitrification, slow freezing, and freeze-drying microencapsulation techniques. In addition, we highlight bioflavonoid extraction techniques, medicinal properties, challenges, and future perspectives of cryopreservation and microencapsulation of bioflavonoids. Regardless of the uniqueness of cryopreservation and microencapsulation as methods to preserve bioflavonoid sources and bioflavonoids' bioactivity, there are challenges reported. Freeze-drying technology is costly. Cryoprotectants damage the integrity of plant cells, to say the least. Researchers are working very hard to overcome these challenges. Encapsulating bioflavonoids via coaxial electrospray and then cryopreserving the micro/nanocapsules produced can be very interesting.

Therapeutic prospects of naturally occurring p38 MAPK inhibitors tanshinone IIA and pinocembrin for the treatment of SARS-CoV-2-induced CNS complications

P38 mitogen-activated protein kinase (p38 MAPK) signaling pathway is closely related to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) replication and hyperinflammatory responses in coronavirus disease 2019 (COVID-19). Therefore, blood-brain barrier-penetrating p38 MAPK inhibitors have good potential for the treatment of central nervous system (CNS) complications of COVID-19. The aim of the present study is the characterization of the therapeutic potential of tanshinone IIA and pinocembrin for the treatment of CNS complications of COVID-19. Studies published in high-quality journals indexed in databases Scopus, Web of Science, PubMed, and so forth were used to review the therapeutic capabilities of selected compounds. In continuation of our previous efforts to identify agents with favorable activity/toxicity profiles for the treatment of COVID-19, tanshinone IIA and pinocembrin were identified with a high ability to penetrate the CNS. Considering the nature of the study, no specific time frame was determined for the selection of studies, but the focus was strongly on studies published after the emergence of COVID-19. By describing the association of COVID-19-induced CNS disorders with p38 MAPK pathway disruption, this study concludes that tanshinone IIA and pinocembrin have great potential for better treatment of these complications. The inclusion of these compounds in the drug regimen of COVID-19 patients requires confirmation of their effectiveness through the conduction of high-quality clinical trials.

Eriodictyol attenuates Furan induced testicular toxicity in Rats: Role of oxidative stress, steroidogenic enzymes and apoptosis

Furan (C₄H₄O) is a naturally occurring organic compound. It develops as a result of the thermal processing of food and stimulates critical impairments in male reproductive tract. Eriodictyol (Etyol) is a natural dietary flavonoid possessing diverse pharmacological potentials. The recent investigation was proposed to ascertain the ameliorative potential of eriodictyol against furan-instigated reproductive dysfunctions. Male rats (n = 48) were classified into 4 groups: untreated/control, furan (10 mg/kg), furan+ eriodictyol (10 mg/kg + 20 mg/kg) and eriodictyol (20 mg/kg). At the 56th day of the trial, the protective effects of eriodictyol were evaluated by assessing various parameters. Results of the study revealed that eriodictyol attenuated furan-induced testicular toxicity in the biochemical profile by increasing catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) along with glutathione reductase (GSR) activities, whereas reduced the reactive oxygen species (ROS) along with malondialdehyde (MDA) levels. It also restored the normal state of sperm motility, viability, the count of hypo-osmotic tail swelled sperm as well as epididymal sperm number along with reduced sperm anomalies (morphological) tail, mid-piece and head. Furthermore, it elevated the decreased levels of luteinizing hormone (LH), plasma testosterone and follicle-stimulating hormone (FSH) as well steroidogenic enzymes (17β-HSD, StAR protein & 3β-HSD) and testicular anti-apoptotic marker (Bcl-2) expression, whereas, down-regulating apoptotic markers (Bax & Caspase-3) expression. Eriodictyol treatment also effectively mitigated the histopathological damages. The outcomes of the current study provide fundamental insights into the ameliorative potential of eriodictyol against furan-instigated testicular toxicity.

Beneficial effects of Chrysin on Cadmium-induced nephrotoxicity in rats: Modulating the levels of Nrf2/HO-1, RAGE/NLRP3, and Caspase-3/Bax/Bcl-2 signaling pathways

Cadmium (Cd) is a toxic heavy metal that targets the kidney directly in the body. Chrysin (CHR) is a natural flavonoid with many properties such as antioxidant, anti-inflammatory and anti-apoptotic. The current study discloses new evidence as regards of the curative effects of CHR on Cd-induced nephrotoxicity by regulating oxidative stress, apoptosis, autophagy, and inflammation. Cd was administered orally at a dose of 25 mg/kg body weight alone or in combination with orally administered CHR (25 and 50 mg/kg body weight) for 7 days. Biochemical, molecular, and histological methods were used to investigate inflammation, apoptosis, autophagy, and oxidant pathways in renal tissue. Renal function tests were also evaluated. Cd caused an increase in serum toxicity markers, lipid peroxidation and a decrease in the activities of antioxidant enzymes. Nrf-2 triggered inflammatory responses by suppressing HO-1 and NQO1 mRNA transcripts and increasing NF-κB, TNF-α, IL-1β and iNOS mRNA transcripts. Cd caused inflammasome by increasing RAGE and NLRP3 mRNA transcripts. In addition, Cd application caused apoptosis by increasing Bax, Apaf-1 and Caspase-3 mRNA transcripts and decreasing Bcl-2 mRNA transcript level. It caused autophagy by increasing the activity of Beclin-1 level. CHR treatment had the opposite effect on all these values and reduced the damage caused by all these signal pathways. Overall, the data of this study indicate that renal damage associated with Cd toxicity could be ameliorated by CHR administration.

Roflumilast escalates α-synuclein aggregate degradation in rotenone-induced Parkinson's disease in rats: Modulation of the ubiquitin-proteasome system and endoplasmic reticulum stress

Perturbation of the protein homeostasis circuit is one of the principal attributes associated with many neurodegenerative disorders, such as Parkinson's disease (PD). This study aimed to explore the neuroprotective effect of roflumilast (ROF), a phosphodiesterase-4 inhibitor, in a rotenone-induced rat model of PD and investigate the potential underlying mechanisms. Interestingly, ROF (1 mg/kg, p.o.) attenuated motor impairment, prevented brain lesions, and rescued the dopaminergic neurons in rotenone-treated rats. Furthermore, it reduced misfolded α-synuclein burden. ROF also promoted the midbrain cyclic adenosine monophosphate level, which subsequently enhanced the 26S proteasome activity and the expression of the 20S proteasome. ROF counteracted rotenone-induced endoplasmic reticulum stress, which was demonstrated by its impact on activating transcription factor 6, glucose-regulated protein 78, and C/EBP homologous protein levels. Moreover, ROF averted rotenone-induced oxidative stress, as evidenced by its effects on the levels of nuclear factor erythroid 2-related factor 2, heme oxygenase-1, reduced glutathione, and lipid peroxides with a significant anti-apoptotic activity. Collectively, this study implies repurposing of ROF as a novel neuroprotective drug owning to its ability to restore normal protein homeostasis.

Activation of Nrf2 pathway as a protective mechanism against oxidative stress-induced diseases: Potential of astaxanthin

Astaxanthin, a red-orange liposoluble carotenoid, has been the centre of considerable attention in recent years for its numerous biological activities, notably its potent antioxidant activity. It is reported that astaxanthin elicits these biological activities via a number of cellular pathways. The Nrf2/Keap1 pathway is a major regulator of the antioxidant defence system of cells; it modulates the expression of a plethora of genes related to redox homeostasis as well as cellular detoxification. The pathway has received lots of attention as a prospective therapeutic target for diseases related to oxidative stress and aging. Several reports have shown that the pathway is inducible by many natural compounds. This present work reviews the Nrf2/Keap1 pathway, its regulation and involvement in diseases, provides a brief overview of naturally occurring compounds as activators of the pathway as well as discusses the effect of astaxanthin on the pathway.

An Analysis of the Toxicity, Antioxidant, and Anti-Cancer Activity of Cinnamon Silver Nanoparticles in Comparison with Extracts and Fractions of Cinnamomum Cassia at Normal and Cancer Cell Levels

In this work, the extract of cinnamon bark was used for the green synthesis of cinnamon-Ag nanoparticles (CNPs) and other cinnamon samples, including ethanolic (EE) and aqueous (CE) extracts, chloroform (CF), ethyl acetate (EF), and methanol (MF) fractions. The polyphenol (PC) and flavonoid (FC) contents in all the cinnamon samples were determined. The synthesized CNPs were tested for the antioxidant activity (as DPPH radical scavenging percentage) in Bj-1 normal cells and HepG-2 cancer cells. Several antioxidant enzymes, including biomarkers, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and reduced glutathione (GSH), were verified for their effects on the viability and cytotoxicity of normal and cancer cells. The anti-cancer activity depended on apoptosis marker protein levels (Caspase3, P53, Bax, and Pcl2) in normal and cancerous cells. The obtained data showed higher PC and FC contents in CE samples, while CF showed the lowest levels. The IC₅₀ values of all investigated samples were higher, while their antioxidant activities were lower than those of vitamin C (5.4 g/mL). The CNPs showed lower IC₅₀ value (55.6 µg/mL), whereas the antioxidant activity inside or outside the Bj-1 or HepG-2 was found to be higher compared with other samples. All samples execrated a dose-dependent cytotoxicity by decreasing the cells' viability percent of Bj-1 and HepG-2. Similarly, the anti-proliferative potency of CNPs on Bj-1 or HepG-2 at different concentrations was more effective than that of other samples. Higher concentrations of the CNPs (16 g/mL) showed greater cell death in Bj-1 (25.68%) and HepG-2 (29.49%), indicating powerful anti-cancer properties of the nanomaterials. After 48 h of CNPs treatment, both Bj-1 and HepG-2 showed significant increases in biomarker enzyme activities and reduced glutathione compared with other treated samples or untreated controls (p < 0.05). The anti-cancer biomarker activities of Caspas-3, P53, Bax, and Bcl-2 levels were significantly changed in Bj-1 or HepG-2 cells. The cinnamon samples were significantly increased in Caspase-3, Bax, and P53, while there were decreased Bcl-2 levels compared with control.

Integrated metabolomics and proteomics analysis to study the changes in Scutellaria baicalensis at different growth stages

Scutellaria baicalensis is a functional food that has the potential to treat various diseases. Scutellaria baicalensis can be divided into two types: Ziqin (strip types) and (rotten xylem). Ziqin is used to clear lower energizer large intestine heat syndrome, while Kuqin is used for the treatment of upper energizer lung heat syndrome. At present, the substance basis of the differences between Ziqin and Kuqin is not clear. The changes in metabolite accumulation and protein expression between them were analyzed by the non-targeted metabolomic technique in combination with the label-free proteomics approach. The results showed that the differentially accumulated metabolites and abundant proteins were mainly enriched in the pathways of phenylalanine, tyrosine and tryptophan biosynthesis, phenylpropanoid biosynthesis, flavonoid biosynthesis, flavone and flavonol biosynthesis, isoflavonoid biosynthesis, and anthocyanin biosynthesis. Collectively, these results reveal the changes of Scutellaria baicalensis in different growth years and provide a reference for selecting the appropriate harvest period.

Capsaicin protects against septic acute liver injury by attenuation of apoptosis and mitochondrial dysfunction

Capsaicin is the main pungent bioactive constituent in red chili with promising therapeutic properties due to its anti-oxidative and anti-inflammatory effects. No evidence exists on the beneficial effect of capsaicin on apoptosis and mitochondrial function in acute liver injury (ALI) under septic conditions. For inducing septic ALI, lipopolysaccharide (LPS, 50 μg/kg) and d-galactose (D-Gal, 400 mg/kg) was intraperitoneally injected and capsaicin was given orally at 5 or 20 mg/kg. Functional markers of liver function and mitochondrial dysfunction were determined as well as hepatic assessment of apoptotic, oxidative, and inflammatory factors. Capsaicin at the higher dose appropriately decreased serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in addition to reducing hepatic level of malondialdehyde (MDA), reactive oxygen species (ROS), nitrite, NF-kB, TLR4, IL-1β, TNF-α, caspase 3, DNA fragmentation and boosting sirtuin 1, Nrf2, superoxide dismutase (SOD) activity, and heme oxygenase (HO-1). These beneficial effects of capsaicin were associated with reversal and/or improvement of gene expression for pro-apoptotic Bax, anti-apoptotic Bcl2, mitochondrial and metabolic regulators PGC-1α, sirtuin 1, and AMPK, and inflammation-associated factors. Additionally, capsaicin exerted a hepatoprotective effect, as revealed by its reduction of liver histopathological changes. These findings evidently indicate hepatoprotective property of capsaicin under septic conditions that can be attributed to its down-regulation of oxidative and inflammatory processes besides its potential to attenuate mitochondrial dysfunction and apoptosis.

Polyphenols Mediate Neuroprotection in Cerebral Ischemic Stroke-An Update

Stroke is one of the main causes of mortality and disability, and it is due to be included in monetary implications on wellbeing frameworks around the world. Ischemic stroke is caused by interference in cerebral blood flow, leading to a deficit in the supply of oxygen to the affected region. It accounts for nearly 80-85% of all cases of stroke. Oxidative stress has a significant impact on the pathophysiologic cascade in brain damage leading to stroke. In the acute phase, oxidative stress mediates severe toxicity, and it initiates and contributes to late-stage apoptosis and inflammation. Oxidative stress conditions occur when the antioxidant defense in the body is unable to counteract the production and aggregation of reactive oxygen species (ROS). The previous literature has shown that phytochemicals and other natural products not only scavenge oxygen free radicals but also improve the expressions of cellular antioxidant enzymes and molecules. Consequently, these products protect against ROS-mediated cellular injury. This review aims to give an overview of the most relevant data reported in the literature on polyphenolic compounds, namely, gallic acid, resveratrol, quercetin, kaempferol, mangiferin, epigallocatechin, and pinocembrin, in terms of their antioxidant effects and potential protective activity against ischemic stroke.

Anti-Inflammatory Therapeutic Mechanisms of Natural Products: Insight from Rosemary Diterpenes, Carnosic Acid and Carnosol

Carnosic acid (CA) and carnosol (CAR) are two major diterpenes of the rosemary plant (Rosmarinus officinalis). They possess a phenolic structural moiety and are endowed with the power to remove cellular reactive oxygen species (ROS) either through direct scavenging reaction or indirectly through upregulation of antioxidant defences. Hand in hand with these activities are their multiple biological effects and therapeutic potential orchestrated through modulating various signalling pathways of inflammation, including the NF-κB, MAPK, Nrf2, SIRT1, STAT3 and NLRP3 inflammasomes, among others. Consequently, they ameliorate the expression of pro-inflammatory cytokines (e.g., TNF-α, IL-1 and IL-6), adhesion molecules, chemokines and prostaglandins. These anti-inflammatory mechanisms of action as a therapeutic link to various effects of these compounds, as in many other natural products, are scrutinised.

Could Naringenin Participate as a Regulator of Obesity and Satiety?

Obesity is a serious health problem worldwide, since it is associated with multiple metabolic disorders and complications such as cardiovascular disease, type 2 diabetes, fatty liver disease and overall metabolic dysfunction. Dysregulation of the hunger-satiety pathway, which includes alterations of central and peripheral signaling, explains some forms of obesity by favoring hyperphagia and weight gain. The present work comprehensively summarizes the mechanisms by which naringenin (NAR), a predominant flavanone in citrus fruits, could modulate the main pathways associated with the development of obesity and some of its comorbidities, such as oxidative stress (OS), inflammation, insulin resistance (IR) and dyslipidemia, as well as the role of NAR in modulating the secretion of enterohormones of the satiety pathway and its possible antiobesogenic effect. The results of multiple in vitro and in vivo studies have shown that NAR has various potentially modulatory biological effects against obesity by countering IR, inflammation, OS, macrophage infiltration, dyslipidemia, hepatic steatosis, and adipose deposition. Likewise, NAR is capable of modulating peptides or peripheral hormones directly associated with the hunger-satiety pathway, such as ghrelin, cholecystokinin, insulin, adiponectin and leptin. The evidence supports the use of NAR as a promising alternative to prevent overweight and obesity.

Neuroprotective Potentials of Flavonoids: Experimental Studies and Mechanisms of Action

Neurological and neurodegenerative diseases, particularly those related to aging, are on the rise, but drug therapies are rarely curative. Functional disorders and the organic degeneration of nervous tissue often have complex causes, in which phenomena of oxidative stress, inflammation and cytotoxicity are intertwined. For these reasons, the search for natural substances that can slow down or counteract these pathologies has increased rapidly over the last two decades. In this paper, studies on the neuroprotective effects of flavonoids (especially the two most widely used, hesperidin and quercetin) on animal models of depression, neurotoxicity, Alzheimer's disease (AD) and Parkinson's disease are reviewed. The literature on these topics amounts to a few hundred publications on in vitro and in vivo models (notably in rodents) and provides us with a very detailed picture of the action mechanisms and targets of these substances. These include the decrease in enzymes that produce reactive oxygen and ferroptosis, the inhibition of mono-amine oxidases, the stimulation of the Nrf2/ARE system, the induction of brain-derived neurotrophic factor production and, in the case of AD, the prevention of amyloid-beta aggregation. The inhibition of neuroinflammatory processes has been documented as a decrease in cytokine formation (mainly TNF-alpha and IL-1beta) by microglia and astrocytes, by modulating a number of regulatory proteins such as Nf-kB and NLRP3/inflammasome. Although clinical trials on humans are still scarce, preclinical studies allow us to consider hesperidin, quercetin, and other flavonoids as very interesting and safe dietary molecules to be further investigated as complementary treatments in order to prevent neurodegenerative diseases or to moderate their deleterious effects.

Current advances on the therapeutic potential of pinocembrin: An updated review

Pinocembrin (5,7-dihydroxyflavone) is a major flavonoid found in many plants, fungi and hive products, mainly honey and propolis. Several in vitro and preclinical studies revealed numerous pharmacological activities of pinocembrin including antioxidant, anti-inflammatory, antimicrobial, neuroprotective, cardioprotective and anticancer activities. Here, we comprehensively review and critically analyze the studies carried out on pinocembrin. We also discuss its potential mechanisms of action, bioavailability, toxicity, and clinical investigations. The wide therapeutic window of pinocembrin makes it a promising drug candidate for many clinical applications. We recommend some future perspectives to improve its pharmacokinetic and pharmacodynamic properties for better delivery that may also lead to new therapeutic advances.

Protective effects of zingerone against sodium arsenite-induced lung toxicity: A multi-biomarker approach

Objectives

Sodium arsenite (SA) exposure is toxic to the body. Zingerone (ZNG) is a flavonoid with many biological properties found naturally in honey and plants. This study aimed to determine the effects of ZNG on SA-induced rat lung toxicity.

Materials and Methods

Thirty-five male Sprague rats were divided into Control, SA, ZNG, SA+ZNG25, and SA+ZNG50 groups (n=7). SA 10 mg/kg and ZNG were administered at two doses (25 and 50 mg/kg) (orally, 14 days). Analysis of oxidative stress, inflammation damage, apoptosis damage, and autophagic damage markers in lung tissue were determined by biochemical and histological methods.

Results

The administration of ZNG reduced oxidative stress by increasing SA-induced decreased antioxidant enzyme activities, increasing Nrf-2, HO-1, and NQO1, and decreasing MDA level. ZNG administration reduced inflammation marker levels. Anti-apoptotic Bcl-2 increased and apoptotic Bax and Caspase-3 decreased with ZNG. ZNG promoted the regression of autophagy by reducing Beclin-1, LC3A, and LC3B levels.

Conclusion

Evaluating all data showed that SA caused toxic damage to lung tissue by increasing inflammation, apoptosis, autophagy, and oxidant levels, whereas ZNG had a protective effect by reducing this damage.

Naringenin attenuates inflammation, apoptosis, and ferroptosis in silver nanoparticle-induced lung injury through a mechanism associated with Nrf2/HO-1 axis: In vitro and in vivo studies

With the wide application of silver nanoparticles (AgNPs), their potential damage to human health needs to be investigated. Lung is one of the main target organs after inhalation of AgNPs. Naringenin has been reported to have anti-inflammatory and anti-oxidative properties. This study aims to evaluate the protective effects of naringenin against AgNPs-induced lung injury and determine the underlying mechanism. In in vivo experiments, AgNPs were intratracheally instilled into ICR mice (l mg/kg) to establish a lung injury model. These mice were then treated with naringenin by oral gavage (25, 50, 100 mg/kg) for three days. Naringenin treatment decreased the levels of white blood cells, neutrophils, and lymphocytes in the blood, ameliorated lung injury, suppressed the release of pro-inflammatory cytokines, normalized ferroptotic markers and prevented oxidative stress with elevating Nrf2 and HO-1 protein expressions in lung. In in vitro experiments, BEAS-2B cells were firstly treated with AgNPs (320 μg/mL) and then naringenin (25, 50, and 100 μM), respectively. Naringenin attenuated AgNPs-induced oxidative stress and inflammatory response. Moreover, naringenin attenuated AgNPs-induced apoptosis with modulated low BAX, CytC, cleaved Caspase9, cleaved Caspase3 but high Bcl2. Furthermore, naringenin effectively decreased ferroptotic markers and increased the protein expressions of Nrf2 and HO-1, as well as increased the nuclear translocation of Nrf2. Importantly, the anti-apoptotic and anti-ferroptotic effects of naringenin in BEAS-2B cells were found to be at least partially Nrf2-dependent. These results indicated that naringenin exerted anti-inflammation, anti-apoptosis, and anti-ferroptosis effects and protected against AgNPs-induced lung injury at least partly via activating Nrf2/HO-1 signaling pathway.

Ergothioneine and its prospects as an anti-ageing compound

Healthy ageing is a crucial process that needs to be highlighted as it affects the quality of lifespan. An increase in oxidative stress along with ageing is the major factor related to the age-associated diseases, especially neurodegenerative disorders. An antioxidant-rich diet has been proven to play a significant role in the ageing process. Targeting ageing mechanisms could be a worthwhile approach to improving health standards. Ergothioneine (EGT), a hydrophilic compound with specific transporter known as OCTN1, has been shown to exert anti-ageing properties. In addition to its antioxidant effect, EGT has been reported to have anti-senescence, anti-inflammatory and anti-neurodegenerative properties. This review aims to define the pivotal role of EGT in major signalling pathways in ageing such as insulin/insulin-like growth factor (IGF) signalling (IIS), sirtuin 6 (SIRT6) and mammalian target of rapamycin complex (mTOR) pathways. The review further discusses evidence of EGT on neurodegeneration in its therapeutic context in various model organisms, providing new insights into improving health. In conclusion, an ergothioneine-rich diet may be beneficial in preventing age-related diseases, resulting in a healthy ageing population.

Neuroprotective effects of hawthorn leaf flavonoids in Aβ 25–35 ‐induced Alzheimer's disease model

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by β-amyloid (Aβ) plaques, neurofibrillary tangles, neuronal cell loss, and oxidative stress. Further deposition of Aβ in the brain induces oxidative stress, neuroinflammation, and memory dysfunction. Hawthorn (Crataegus pinnatifida Bge.) leaf, a known traditional Chinese medicine, is commonly used for the treatment of hyperlipidemia, heart palpitations, forgetfulness, and tinnitus, and its main bioactive components are Hawthorn Leaf Flavonoids (HLF). In this study, we investigated the neuroprotective effects of the HLF on the Aβ_25-35 (bilateral hippocampus injection) rat model of AD. The results showed that the oral administration of HLF at a dose of 50, 100, and 200 mg/kg for 30 days significantly ameliorated neuronal cell damage and memory deficits, and markedly increased the enzyme activities of superoxide dismutase and catalase, and the content of glutathione whereas it decreased the malondialdehyde content in the Aβ_25-35 rat model of AD as well as suppressed the activation of astrocytes. In addition, HLF up-regulated Nrf-2, NQO-1, and HO-1 protein expressions. Also, it reduced neuroinflammation by inhibiting activation of astrocytes. In summary, these results indicated that HLF decreased the oxidative stress via activating Nrf-2/antioxidant response element signaling pathways, and may suggest as a potential candidate for AD therapeutic agent.

Bacillus subtilis-Fermented Amomum xanthioides Ameliorates Metabolic-Syndrome-Like Pathological Conditions in Long-Term HFHFD-Fed Mice

In modern society, numerous metabolic disorders are widespread globally. The present study aimed to demonstrate whether Bacillus subtilis-fermented Amomum xanthioides (BSAX) exerts anti-metabolic disturbance effects compared with the ethyl acetate fraction of Amomum xanthioides (EFAX), a previously verified functional fraction. Mice fed with a high-fat, high-fructose diet (HFHFD) for 10 wk presented a typical model of metabolic dysfunction, and BSAX significantly attenuated a string of metabolic-syndrome-related pathological parameters, such as body, fat, organ mass, lipid markers (TGs, TC, free fatty acids), and glucose metabolism (glucose, insulin), without influencing appetite. Further, BSAX markedly lowered malondialdehyde (MDA) and ROS in the blood and restored antioxidative parameters (SOD, GSH, and CAT in liver tissue, and total bilirubin in serum) by elevating Nrf2 and HO-1. Moreover, BSAX noticeably restored gut microbiota diversity and normalized lipid-metabolism-associated proteins, including SREBP-1, p-AMPK, and PPAR-α. Generally, most metabolic parameters were improved by BSAX to a greater extent than EFAX, except for liver weight and hepatic TC. In conclusion, BSAX alleviates metabolic dysfunction by enhancing lipid metabolism and antioxidative capacity and is more effective than EFAX. Therefore, the application of high-yield, effective BSAX might be a promising approach for curing and preventing metabolic disorders.

Naringenin Alleviates Renal Ischemia Reperfusion Injury by Suppressing ER Stress-Induced Pyroptosis and Apoptosis through Activating Nrf2/HO-1 Signaling Pathway

Endoplasmic reticulum (ER) stress, pyroptosis, and apoptosis are critical molecular events in the occurrence and progress of renal ischemia reperfusion (I/R) injury. Naringenin (4′,5,7-trihydroxyflavanone) is one of the most widely consumed flavonoids with powerful antioxidant and anti-inflammatory activities. However, whether naringenin is able to relieve renal I/R injury and corresponding mechanisms have not been fully clarified. This study was aimed at exploring its role and relevant mechanisms in renal I/R injury. The C57Bl/6 mice were randomly assigned to receive administration with naringenin (50 mg/kg/d) or sterile saline (1.0 mL/d) for 3 d by gavage and suffered from renal I/R surgery. One specific ER stress inhibitor, 4-phenylbutyric acid (4-PBA, 100 mg/kg/d), was intraperitoneally administered to validate the regulation of ER stress on pyroptosis and apoptosis. Cultured HK-2 cells went through the process of hypoxia/reoxygenation (H/R) to perform cellular experiments with the incubation of naringenin (200 μM), 4-PBA (5 mM), or brusatol (400 nM). The animal results verified that naringenin obviously relieved renal I/R injury, while it refined renal function and attenuated tissue structural damage. Furthermore, naringenin treatment inhibited I/R-induced ER stress as well as pyroptosis and apoptosis as indicated by decreased levels of specific biomarkers such as GRP78, CHOP, caspase-12, NLRP3, ASC, caspase-11, caspase-4, caspase-1, IL-1β, GSDMD-N, BAX, and cleaved caspase-3 in animals and HK-2 cells. Besides, the upregulated expression of Nrf2 and HO-1 proteins after naringenin treatment suggested that naringenin activated the Nrf2/HO-1 signaling pathway, which was again authenticated by the usage of brusatol (Bru), one unique inhibitor of the Nrf2 pathway. Importantly, the application of 4-PBA showed that renal I/R-generated pyroptosis and apoptosis were able to be regulated by ER stress in vivo and in vitro. In conclusion, naringenin suppressed ER stress by activating Nrf2/HO-1 signaling pathway and further alleviated pyroptosis and apoptosis to protect renal against I/R injury.

Neuroprotective effect of Geijigadaehwang-tang against trimethyltin-induced hippocampal neurodegeneration: An in vitro and in vivo study

ETHNOPHARMACOLOGICAL RELEVANCE

Patients with dementia are diagnosed with deficiency patterns and interior patterns in traditional Chinese medicine due to decreased physical strength, mental atrophy including cognitive function, and decreased motor function in the gastrointestinal tract. Since "greater yin symptom" in Shanghanlun has been interpreted as interior, deficiency, and cold pattern in traditional Chinese medicine, it is necessary to determine whether Geijigadaehwang-tang (GDT) has therapeutic effects on neurodegenerative diseases and the underlying mechanism if it has such effects.

AIMS OF THE STUDY

Trimethyltin (TMT), a neurotoxic organotin compound, has been used to induce several neurodegenerative diseases, including epilepsy and Alzheimer's disease. This study aimed to evaluate the therapeutic efficacy of GDT for TMT-induced hippocampal neurodegeneration and seizures and to determine the mechanisms involved at the molecular level.

MATERIALS AND METHODS

The main components of GDT were analyzed using ultra-performance liquid chromatography. TMT was used to induce neurotoxicity in microglial BV-2 cells and C57BL6 mice. GDT was administered at various doses to determine its neuroprotective and seizure inhibition effects. The inhibitory effects of GDT on TMT-induced apoptosis, inflammatory pathways, and oxidative stress pathways were determined in the mouse hippocampal tissues.

RESULTS

GDT contained emodin, chrysophanol, albiflorin, paeoniflorin, 6-gingerol, and liquiritin apioside. In microglial BV-2 cells treated with TMT, GDT showed dose-dependent neuroprotective effects. Oral administration of GDT five times for 2.5 days before and after TMT injection inhibited seizures at doses of 180 and 540 mg/kg and inhibited neuronal death in the hippocampus. In hippocampal tissues extracted from mice, GDT inhibited the protein expression of ionized calcium binding adaptor molecule 1, glial fibrillary acidic protein, nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing protein 3, and phosphorylated nuclear factor (NF)-κB/total-NFκB ratio. Additionally, GDT inhibited the messenger RNA levels of tumor necrosis factor-α, inducible nitric oxide synthase, apoptosis-associated speck-like protein containing a caspase recruitment domain, caspase-1, interleukin-1β, nuclear factor erythroid-2-related factor 2, and heme oxygenase-1.

CONCLUSION

This study's results imply that GDT might have neuroprotective potential in neurodegenerative diseases through neuronal death inhibition and anti-inflammatory and antioxidant mechanisms.

Naringenin protects against iron overload-induced osteoarthritis by suppressing oxidative stress

BACKGROUND

The traditional Chinese medicine Gusuibu, the rhizome of Rhizoma Drynariae, is used to treat rheumatism and fractures. Naringenin (NAR) is an active ingredient in Gusuibu and has significant anti-inflammatory and antioxidant effects. However, the role of naringenin in iron overload-induced osteoarthritis (IOOA) is unknown.

HYPOTHESIS

NAR reduces cartilage damage in IOOA.

METHODS

The effects of NAR on the viability of IOOA chondrocytes and the synthesis ability of type II collagen were evaluated using cell counting kit (CCK8) and toluidine blue assays. To determine the mechanism of action and characteristics of NAR, the intracellular iron ion content, apoptosis rate, and mitochondrial membrane potential (MMP) change, and malondialdehyde (MDA) levels, as well as the degree of reactive oxygen species (ROS) and lipid hydroperoxide (LPO) accumulation in the cells were detected in vitro and verified using western blotting and quantitative real-time PCR (qRT-PCR). To verify the role of NAR in vivo, IOOA mice were established using iron dextran and surgery-induced destabilised medial meniscus. Changes in the articular cartilage and subchondral bone were examined using Safranin O-fast Green staining (S-O), haematoxylin-eosin staining (H&E), and microcomputed tomography (μCT).

RESULTS

In vitro, NAR attenuated the impairment of cell viability, apoptosis, and MMP caused by ferric ammonium citrate and interleukin-1β co-culture, increased the levels of MDA, reduced the expression of matrix metallopeptidase (MMP)3, MMP13, and Bax, and restored the expression of type II collagen (Col II). NAR showed a slight iron accumulation-reducing effect. NAR alleviated the accumulation of ROS and LPO in IOOA chondrocytes and upregulated antioxidant genes nuclear factor E2-related factor 2 (NRF2) and haem oxygenase 1 (HO-1). When ML385, a specific NRF-2 inhibitor, was added, the protective effect of NAR was significantly inhibited. In vivo, NAR reduced synovitis and attenuated cartilage damage and subchondral bone proliferation in IOOA mice.

CONCLUSIONS

NAR can reduce oxidative stress through the NRF2-HO-1 pathway, alleviate cartilage damage under iron overload, and has the potential to treat IOOA.

Aspergillus awamori attenuates ochratoxin A-induced renal and cardiac injuries in rabbits by activating the Nrf2/HO-1 signaling pathway and downregulating IL1β, TNFα, and iNOS gene expressions

Ochratoxin A (OTA) is one of the most dangerous and that pollute agricultural products, inducing a variety of toxic effects in humans and animals. The current study explored the protective effect of different concentrations of Aspergillus awamori (A. awamori) against OTA (0.3 mg/kg diet) induced renal and cardiac damage by exploring its mechanism of action in 60 New Zealand white male rabbits. Dietary supplementation of A. awamori at the selected doses of 50, 100, and 150 mg/kg diet, respectively, for 2 months significantly improved the rabbit's growth performance; modulated the suppressed immune response and restored the altered hematological parameters; reduced the elevated levels of renal injury biomarkers such as urea, creatinine, and alkaline phosphatase; and increased serum total proteins concentrations. Moreover, it also declined enzymatic activities of cardiac injury biomarkers, including AST, LDH, and CK-MB. A. awamori alleviated OTA-induced degenerative and necrotic changes in the kidney and heart of rabbits. Interestingly, A. awamori upregulated Nrf2/OH-1 signaling pathway. Therefore enhanced TAC, CAT, and SOD enzyme activities and reduced OTA-induced oxidative and nitrosative stress by declining iNOS gene expression and consequently lowered MDA and NO levels. In addition to attenuating renal and cardiac inflammation via reducing IL-1β, TNF-α gene expressions in a dose-dependent response. In conclusion,this is the first report to pinpoint that dietary incorporation of A. awamori counteracted OTA-induced renal and cardiac damage by potentiating the rabbit's antioxidant defense system through its potent antioxidant, free radical scavenging, and anti-inflammatory properties in a dose-dependent response. Based on our observations, A. awamori could be utilized as a natural protective agent against ochratoxicosis in rabbits.

Proanthocyanidins Activate Nrf2/ARE Signaling Pathway in Intestinal Epithelial Cells by Inhibiting the Ubiquitinated Degradation of Nrf2

Nrf2 plays a key role in the antioxidant system, and many antioxidants can activate the Nrf2/ARE signaling pathway and alleviate oxidative stress. However, the underlying mechanisms of antioxidants, such as proanthocyanidin- (PC-) induced Nrf2 activation, remain poorly understood. In this study, PC was used on MODE-K cells at different concentrations (0, 1, 2.5, and 5 μg/mL) and different times (0, 3, 6, 12, and 24 h); then, immunoprecipitation, immunofluorescence, and Western blotting were performed to test Nrf2, Bach1, Keap1, HO-1, and NQO1 protein expressions in MODE-K cells. Results showed that PC increased Nrf2, HO-1, and NQO1 protein expressions, decreased Keap1 and Bach1 protein expressions, and enhanced ARE gene activity. PC also decreased the ubiquitinated degradation of the Nrf2 protein, increased Nrf2 protein stability, and increased Nrf2 protein expression by inhibiting Keap1-dependent Nrf2 protein degradation, promoted Nrf2 entry into the nucleus, competed with Bach1, and activated ARE elements, which in turn initiated the Nrf2/ARE signaling pathway. Thus, we conclude that PC activates the Nrf2/ARE signaling pathway in intestinal epithelial cells by inhibiting the ubiquitinated degradation of Nrf2, increasing Nrf2 protein stability and expression, and then regulating key antioxidant enzymes such as HO-1 and NQO1 to initiate cytoprotective effects.

Eriodictyol inhibits breast carcinogenesis by targeting circ_0007503 and repressing PI3K/Akt pathway

BACKGROUND

Eriodictyol in citrus fruits, Eriodictyon californicum and several Chinese herbal medicines shows great promise for chronic disease prevention, including cancers. However, its role in chemopreventive activities against breast carcinogenesis is unknown.

PURPOSE

In the present study, we investigated the chemopreventive effect and the underlying mechanism of eriodictyol on carcinogens-induced breast carcinogenesis in vivo and in vitro.

METHODS

The carcinogenic transformation in MCF10A cells was induced by the environmental carcinogens in vitro. The chemopreventive effect in vivo was evaluated by using the experimental model of 1-methyl-1-nitrosourea (MNU)-induced mammary tumorigenesis in rats. The activation of the PI3K/Akt pathway was detected by western blot assay; the levels of circular RNAs (circRNAs) were measured by qRT-PCR.

RESULTS

First, eriodictyol significantly reduces cells viability and induces apoptosis in breast cancer cells in a dose-dependent manner in vitro (P < 0.05). Next, eriodictyol could effectively suppress environmental carcinogens-induced acquisition of carcinogenic properties in human breast epithelial cell MCF10A (P < 0.05). In vivo, eriodictyol administration reduces the incidence of mammary tumor by 50% in carcinogen-treated female rats (P < 0.05). Further study revealed that eriodictyol represses the PI3K/Akt signaling pathway and down-regulates the level of circ_0007503 in breast cancer cells and in breast carcinogenesis (P < 0.01). When the effect of eriodictyol on circ_0007503 was blocked by transfection of a circ_0007503 over-expression plasmid, the cytotoxic effects and the suppression of the PI3K/Akt pathway of eriodictyol in breast cancer cells were significantly reduced (P < 0.05).

CONCLUSION

Our data indicated that eriodictyol could effectively suppress breast carcinogenesis in vitro and in vivoThe mechanism may be attributed to targeting circ_0007503 and inhibiting PI3K/Akt pathway.

Potential cancer treatment effects of brusatol or eriodictyol combined with 5-fluorouracil (5-FU) in colorectal cancer cell

Colorectal cancer is among the most frequently diagnosed cancers in patients today. In the treatment of this disease, combination or multicomponent therapy has been identified as a potential method to improve patient response and delay side effects. The aim of this study was to determine the effects on cell viability of commercial Bru and Erio used together with the anticancer drug 5-FU in the human colorectal cancer (CRC) cell line (HT-29 cell line) for the first time, as far as can be determined from available literature at this time. Additionally, the research seeks to study any potential effects on apoptosis. For this purpose, the effects of independent and combined treatments of the aforementioned agents on cell viability were investigated through the MTT experiment. Apoptotic effects were determined by Annexin V/PI and real-time PCR methods. In addition, a cell cycle analysis was used to determine the distribution of cells in the cycle. Data from experiments for 48 h showed that Bru, alone or in combination with 5-FU, is capable of causing an increase in the percentage of apoptotic cells in HT-29 cells compared to those of Erio alone or in combination with 5-FU. A significant increase in the level of bax and caspase-3 apoptotic genes was also detected in combinations of IC₅₀ concentrations of Bru and 5-FU. These findings suggest that unlike Erio, Bru alone or in combination with 5-FU may be useful for increasing the effects of 5-FU used in the treatment of CRC and to provide data on alternative treatment approaches.

Biological Potential, Gastrointestinal Digestion, Absorption, and Bioavailability of Algae-Derived Compounds with Neuroprotective Activity: A Comprehensive Review

Currently, there is no known cure for neurodegenerative disease. However, the available therapies aim to manage some of the symptoms of the disease. Human neurodegenerative diseases are a heterogeneous group of illnesses characterized by progressive loss of neuronal cells and nervous system dysfunction related to several mechanisms such as protein aggregation, neuroinflammation, oxidative stress, and neurotransmission dysfunction. Neuroprotective compounds are essential in the prevention and management of neurodegenerative diseases. This review will focus on the neurodegeneration mechanisms and the compounds (proteins, polyunsaturated fatty acids (PUFAs), polysaccharides, carotenoids, phycobiliproteins, phenolic compounds, among others) present in seaweeds that have shown in vivo and in vitro neuroprotective activity. Additionally, it will cover the recent findings on the neuroprotective effects of bioactive compounds from macroalgae, with a focus on their biological potential and possible mechanism of action, including microbiota modulation. Furthermore, gastrointestinal digestion, absorption, and bioavailability will be discussed. Moreover, the clinical trials using seaweed-based drugs or extracts to treat neurodegenerative disorders will be presented, showing the real potential and limitations that a specific metabolite or extract may have as a new therapeutic agent considering the recent approval of a seaweed-based drug to treat Alzheimer’s disease.

Pinocembrin Decreases Atrial Fibrillation Susceptibility in a Rodent Model of Depression

Background

Depression is often comorbid with cardiovascular diseases and contributes to the development and maintenance of atrial fibrillation (AF). Ample research demonstrated that pinocembrin had protective effects on the neuropsychiatric and cardiovascular systems via its pharmacological properties. However, whether pinocembrin protects from AF in depression models is not known. The present research investigated antiarrhythmic effects of pinocembrin and the underlying mechanisms in depressed rats.

Methods

One hundred and ten male Sprague Dawley rats were randomly divided into six groups: the CTL group (the normal rats administered saline), the CTP group (the normal rats administered pinocembrin), the MDD group (the depressed rats administered saline), the MDP group (the depressed rats administered pinocembrin), the MDA group (the depressed rats administered apocynin), and the MPA group (the depressed rats administered both pinocembrin and apocynin). Chronic unpredictable mild stress (CUMS) was performed for 28 days to establish the depression model. Pinocembrin was administered via gavage from Day 8 to Day 28, and apocynin was administered via intraperitoneal injection from Day 1 to Day 28. The effects were evaluated using behavioral measurements, in vitro electrophysiological studies, whole-cell patch-clamp recordings, biochemical detection, Western blot, and histological studies.

Results

Pinocembrin treatment significantly attenuated the abnormality of heart rate variability (HRV), the prolongation of action potential duration (APD), the shortening of the effective refractory period (ERP), the reduction of transient outward potassium current (I_to), and the increase in L-type calcium current (I_Ca–L), which increase susceptibility to AF in a rat model of depression. Compared to the depressed rats, pinocembrin also increased the content of Kv4.2, Kv4.3, and atrial gap junction channel Cx40 and decreased the expression level of Cav1.2, which ameliorated oxidative stress and inhibited the ROS/p-p38MAPK pro-apoptotic pathway and the ROS/TGF-β1 pro-fibrotic pathway.

Conclusion

Pinocembrin is a therapeutic strategy with great promise for the treatment of AF in depressed patients by reducing oxidative stress.

Anti-Photoaging Effect of Hydrolysates from Pacific Whiting Skin via MAPK/AP-1, NF-κB, TGF-β/Smad, and Nrf-2/HO-1 Signaling Pathway in UVB-Induced Human Dermal Fibroblasts

Chronic exposure to ultraviolet (UV) light promotes the breakdown of collagen in the skin and disrupts the extracellular matrix (ECM) structure, leading to skin wrinkling. Pacific whiting (Merluccius productus) is a fish abundant on the Pacific coast. In the current study, we investigated the anti-wrinkle effect of hydrolysate from Pacific whiting skin gelatin (PWG) in UVB-irradiated human dermal fibroblasts and the molecular mechanisms involved. PWG effectively restored type 1 procollagen synthesis reduced by UVB-irradiation. Also, we found that PWG inhibited collagen degradation by inhibiting MMP1 expression. Furthermore, PWG decreased cytokines TNF-α, IL-6, and IL-1β associated with inflammatory responses and increased antioxidant enzymes, HO-1, SOD, GPx, CAT, and GSH content, a defense system against oxidative stress. In terms of molecular mechanisms, PWG increased collagen synthesis through activating the transforming growth factor β (TGF-β)/Smad pathway and decreased collagen degradation through inhibiting the mitogen-activated protein kinases/activator protein 1 (MAPK/AP-1) pathway. It also suppressed the inflammatory response through suppressing the nuclear factor-κB (NF-κB) pathway and increased antioxidant enzyme activity through activating the nuclear factor erythroid 2/heme oxygenase 1 (Nrf-2/HO-1) pathway. These multi-target mechanisms suggest that PWG may serve as an effective anti-photoaging material.

Eriodictyol and Homoeriodictyol Improve Memory Impairment in Aβ25–35-Induced Mice by Inhibiting the NLRP3 Inflammasome

(1) Alzheimer’s disease (AD) is a neurodegenerative disorder, and it is now widely accepted that neuroinflammation plays a key role in its pathogenesis. Eriodictyol (Eri) and homoeriodictyol (Hom), dihydroflavonoids extracted from a variety of plants, have been confirmed to display a relationship with neuroprotection. (2) Methods: An AD mouse model was constructed by intracerebroventricular (ICV) injection of the Aβ_25–35 peptide, and Eri and Hom were administered orally for 4 weeks. UPLC-MS/MS was used to determine whether Eri and Hom cross the blood–brain barrier to exert their therapeutic effects. Histological changes in the brain and levels of Aβ were evaluated, and Y-maze and new object recognition experiments were conducted to assess the effects of Eri and Hom on Aβ_25–35-induced memory impairment in mice. The levels of oxidative stress and apoptosis in peripheral immune cells and progenitor cells in the hippocampal region were analyzed by flow cytometry and in vitro assays. Western blotting and enzyme-linked immunosorbent assays (ELISA) were used to measure the expression levels of NLRP3 inflammasome-related proteins and inflammatory factors in the brain. The effect of nigericin (an agonist of the NLRP3 inflammasome) on Eri and Hom intervention in LPS-induced N9 microglia was examined using a High Content Screening System. (3) Results: Eri and Hom reduced neuronal damage in mouse brain tissue, decreased Aβ levels in the brain, downregulated oxidative stress and apoptosis levels, and improved learning and memory capacity by crossing the blood–brain barrier to exert its effects. Moreover, Eri and Hom inhibited NLRP3 inflammasome activation and ameliorated immune cell disorder. Furthermore, the effect of Eri and Hom on LPS-induced N9 microglia disappeared after the addition of nigericin to agonize NLRP3 receptors. (4) Conclusions: Eri and Hom improved Aβ_25–35-induced memory impairment in mice by inhibiting the NLRP3 inflammasome.

Therapeutic Potential of Isorhamnetin following Acetaminophen-Induced Hepatotoxicity through Targeting NLRP3/NF-κB/Nrf2

Acetaminophen (APAP)-induced acute liver injury (ALI) is the principal cause of acute liver failure (ALF) in some countries including the United States and with few available treatments. Isorhamnetin is a bioflavonoid that is found in medicinal plants like Hippophae rhamnoides L. and Ginkgo biloba L. with promising potential to regulate inflammatory responses. In this study, we evaluated the possible effect of isorhamnetin in prevention of APAP-induced ALI and analyzed further the involvement of oxidative stress and inflammation-associated factors. Male C57BL/6 mice were given isorhamnetin (25 or 100 mg/kg b.w., p.o.) three times at 48, 24, and 1 h before APAP administration (300 mg/kg b.w., i.p.). Functional indicators of liver injury were measured as well as analysis of oxidative stress- and inflammation-associated indices and liver histopathology was also conducted. Isorhamnetin at the higher dose of 100 mg/kg significantly lowered serum levels of ALT, ALP, and AST in addition to reduction of ROS, TBARS, IL-6, TNFα, NF-kB, NLRP3, caspase 1, and MPO and significantly prevented reduction of GSH, SOD activity, sirtuin 1, and Nrf2. Additionally, isorhamnetin alleviated pathological changes of the liver tissue and suitably reversed NF-kB and Nrf2 immunoreactivity. These findings show protective effect of isorhamnetin against acetaminophen-induced liver injury through reducing oxidative stress, inflammation, and pyroptosis which is attributed to its regulation of NF-kB, Nrf2, NLRP3, and sirtuin 1.

Luteolin Synergistically Enhances Antitumor Activity of Oxaliplatin in Colorectal Carcinoma via AMPK Inhibition

Luteolin is a naturally-occurring polyphenolic compound that is known to have antioxidative and antitumor activities in vitro. This study aimed to examine the in vivo anticancer efficacy of luteolin in conjunction with oxaliplatin treatment using a colorectal carcinoma xenograft mouse model. HCT116 human colorectal carcinoma cells were subcutaneously implanted into BALB/c nude mice, followed by the intraperitoneal administration of luteolin at a dose of 50 mg/kg body weight (BW)/day with or without oxaliplatin at a dose of 10 mg/kg BW/day three times per week for a total of 3 weeks. The combined luteolin and oxaliplatin treatment resulted in the synergistic suppression of the growth of HCT116 xenograft tumors when compared to treatment with luteolin or oxaliplatin alone. In addition, the combined treatment significantly increased the expression of cleaved PARP and p53 in the xenograft tumors compared with the vehicle control, but only marginally affected the level of heme oxygenase-1 (HO-1). These results indicated that luteolin treatment retarded oxaliplatin-induced tumor growth by facilitating apoptotic cell death and inhibiting HO-1-mediated cytoprotection. Therefore, these findings suggest the synergistic potential of dietary luteolin in conjunction with conventional chemotherapy for the treatment of colorectal cancer.

A comprehensive analysis of age-related metabolomics and transcriptomics reveals metabolic alterations in rat bone marrow mesenchymal stem cells

The functions of stem cells decline progressively with aging, and some metabolic changes occur during the process. However, the molecular mechanisms of stem cell aging remain unclear. In this study, the combined application of metabolomics and transcriptomics technologies can effectively describe the possible molecular mechanisms of rat bone marrow mesenchymal stem cell (BMSC) senescence. Metabolomic profiles revealed 23 differential metabolites which were abundant in “glycerophospholipid metabolism”, “linoleic acid metabolism” and “biosynthesis of unsaturated fatty acids”. In addition, transcriptomics analysis identified 590 genes with enormously differential expressions in young and old BMSCs. KEGG enrichment analyses showed that metabolism-related pathways in BMSC senescence had stronger responses. Furthermore, the integrated analysis of the interactions between the differentially expressed genes (DEGs) and metabolites indicated the differential genes related to lipid metabolism of Scd, Scd2, Dgat2, Fads2, Lpin1, Gpat3, Acaa2, Lpcat3, Pcyt2 and Pla2g4a may be closely associated with the aging of BMSCs. Finally, Scd2 was identified as the most significant DEG, and Scd2 over-expression could alleviate cellular senescence in aged BMSCs. In conclusion, this work provides a validated understanding that the DEGs and metabolites related to lipid metabolism present more apparent changes in the senescence of rat BMSCs.

The Effect of Dietary Polyphenols on Vascular Health and Hypertension: Current Evidence and Mechanisms of Action

The aim of this review was to explore existing evidence from studies conducted on humans and summarize the mechanisms of action of dietary polyphenols on vascular health, blood pressure and hypertension. There is evidence that some polyphenol-rich foods, including berry fruits rich in anthocyanins, cocoa and green tea rich in flavan-3-ols, almonds and pistachios rich in hydroxycinnamic acids, and soy products rich in isoflavones, are able to improve blood pressure levels. A variety of mechanisms can elucidate the observed effects. Some limitations of the evidence, including variability of polyphenol content in plant-derived foods and human absorption, difficulty disentangling the effects of polyphenols from other dietary compounds, and discrepancy of doses between animal and human studies should be taken into account. While no single food counteracts hypertension, adopting a plant-based dietary pattern including a variety of polyphenol-rich foods is an advisable practice to improve blood pressure.

Hydroxylation decoration patterns of flavonoids in horticultural crops: chemistry, bioactivity and biosynthesis

Flavonoids are the most widespread polyphenolic compounds and are important dietary constituents present in horticultural crops such as fruits, vegetables, and tea. Natural flavonoids are responsible for important quality traits, such as food colors and beneficial dietary antioxidants and numerous investigations have shown that intake of flavonoids can reduce the incidence of various non-communicable diseases (NCDs). Analysis of the thousands of flavonoids reported so far has shown that different hydroxylation modifications affect their chemical properties and nutritional values. These diverse flavonoids can be classified based on different hydroxylation patterns in the B, C, A rings and multiple structure-activity analyses have shown that hydroxylation decoration at specific positions markedly enhances their bioactivities. This review focuses on current knowledge concerning hydroxylation of flavonoids catalyzed by several different types of hydroxylase enzymes. Flavonoid 3'-hydroxylase (F3'H) and flavonoid 3'5'-hydroxylase (F3'5'H) are important enzymes for the hydroxylation of the B ring of flavonoids. Flavanone 3-hydroxylase (F3H) is key for the hydroxylation of the C ring, while flavone 6-hydroxylase (F6H) and flavone 8-hydroxylase (F8H) are key enzymes for hydroxylation of the A ring. These key hydroxylases in the flavonoid biosynthesis pathway are promising targets for the future bioengineering of plants and mass production of flavonoids with designated hydroxylation patterns of high nutritional importance. In addition, hydroxylation in key places on the ring may help render flavonoids ready for degradation, the catabolic turnover of which may open the door for new lines of inquiry.

Anti-Inflammatory Effects of (9Z,11E)-13-Oxooctadeca-9,11-dienoic Acid (13-KODE) Derived from Salicornia herbacea L. on Lipopolysaccharide-Stimulated Murine Macrophage via NF-kB and MAPK Inhibition and Nrf2/HO-1 Signaling Activation

Glasswort (Salicornia herbacea L.) is a halophyte that exhibits antioxidant and antidiabetic effects. Only a few studies have been conducted on its antioxidant effects. Here, we isolated an antioxidant using an activity-based purification method, and the resulting compound was identified as (9Z,11E)-13-Oxooctadeca-9,11-dienoic acid (13-KODE). We investigated its ability to suppress inflammatory responses and the molecular mechanisms underlying these abilities using lipopolysaccharide-stimulated RAW 264.7 macrophage cells. We studied the anti-inflammatory effects of 13-KODE derived from S. herbacea L on RAW 264.7 macrophages. 13-KODE inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production by suppressing inducible NO synthase and suppressed LPS-induced tumor necrosis factor and interleukin-1β expression in RAW 264.7 macrophages. LPS-mediated nuclear localization of NF-κB and mitogen-activated protein kinase activation were inhibited by 13-KODE. 13-KODE significantly reduced LPS-induced production of reactive oxygen species and increased the expression of nuclear factor erythroid-2 like 2 (Nfe2I2) and heme oxygenase 1. Overall, our results indicate that 13-KODE may have potential for treating inflammation.

The role of flavonoids in inhibiting IL-6 and inflammatory arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects the synovial joints. RA has well-known clinical manifestations and can cause progressive disability and premature death along with socioeconomic burdens. Interleukin-6 (IL-6) has been implicated in the pathology of RA where it can stimulate pannus formation, osteoclastogenesis, and oxidative stress. Flavonoids are plant metabolites with beneficial pharmacological effects, including anti-inflammatory, antioxidant, antidiabetic, anticancer, and others. Flavonoids are polyphenolic compounds found in a variety of plants, vegetables, and fruits. Many flavonoids have demonstrated anti-arthritic activity mediated mainly through the suppression of pro-inflammatory cytokines. This review thoroughly discusses the accumulate data on the role of flavonoids on IL-6 in RA.

Pinocembrin relieves hip fracture-induced pain by repressing spinal substance P signaling in aged rats

Whether pinocembrin (PCN) could be utilized to alleviate hip fracture-induced pain is investigated in this research. Aged rats with hip fractures were treated with vehicle or 80 mg/kg/day PCN from week 3 to week 4. Then hind paw mechanical allodynia, unweighting, warmth, and thickness were measured. The microglia and astrocytes activation and proliferation markers in the spinal dorsal horn were detected with real-time PCR and immunofluorescence staining. The relative expression of substance P and its receptor, tachykinin receptor 1 (Tacr1), were detected with enzyme-linked immunosorbent assay (ELISA) and Western blots. The antinociceptive effect of Tacr1 inhibitor LY303870 was also testified. PCN alleviated hip fracture-induced hind paw nociceptive (allodynia and unweighting) and vascular changes (warmth and thickness) in aged rats with diminished microglia and astrocytes activation and proliferation in the spinal dorsal horn. Up-regulated substance P and Tacr1 were induced after hip fracture, which could be reversed by PCN treatment. Furthermore, LY303870 treatment partially reversed both spinal nociceptive sensitization and vascular changes after hip fracture. Substance P signaling contributes to the nociceptive and vascular changes observed in the hip fracture, which could be alleviated by PCN.

WD-40 repeat protein 26 protects against oxidative stress-induced injury in astrocytes via Nrf2/HO-1 pathways

BACKGROUND

Stroke is the leading cause of disability and the third leading cause of death in the world, and no effective treatment has been developed. Oxidative stress-induced cell injury and genomic instability is implicated in the pathogenesis of stroke, whose prognosis remains poor.

METHODS

A model of cerebral ischemic/reperfusion injury model was established through four artery occlusions. This study was carried out using western blot, flow cytometry and RT-PCR on cell line U251-MG. The cytotoxic effect of H₂O₂ and expression of LDH, caspase-3, MDA and SOD was analyzed by assay kit.

RESULTS

We found that the expression of WDR26 was induced in cerebral ischemia-reperfusion injury in vivo and the expression of WDR26 was induced by H₂O₂ in a dose- and time-dependent manner in vitro. WDR26 over-expression significantly suppressed H₂O₂-induced cell death and caspase-3-mediated apoptosis in U251-MG cells. In contrast, inhibition of WDR26 markedly enhanced cell death in U251-MG cells. In addition, WDR26 regulated oxidative stress response and induced Nrf2/HO-1 pathway.

CONCLUSIONS

These findings suggest that WDR26 mediates H₂O₂-induced oxidative stress and cell injury, possibly by reducing the intrinsic apoptotic pathway and activating Nrf2 and HO-1 in astrocytes.

Naringenin protects swine testis cells from bisphenol A-induced apoptosis via Keap1/Nrf2 signaling pathway

Bisphenol A (BPA) has caused serious pathologies in varying organs of humans and animals, especially reproductive organs. Naringenin (NRG) is a flavanone compound that has shown protective effects against several environmental chemicals through suppression of oxidative stress and activation of nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Herein, we described the discovery path of NRG inhibition on apoptosis in BPA exposed swine testis (ST) cells through targeting Kelch-like ech-associated protein (Keap1). We found that NRG could specifically bound to the active residues of DGR domain in Keap1, thereby activating Nrf2 signaling pathway, and then increasing the levels of SOD, GPx and CAT, and finally inhibiting oxidative stress and mitochondrial apoptosis induced by BPA in ST cells. Altogether, our results showed that NRG inhibits oxidative stress and mitochondrial apoptosis induced by BPA in ST cells by targeting Keap1/Nrf2 signaling pathway, indicating that NRG could serve as an antagonistic therapy against BPA.

Propofol inhibits oxidative stress injury through the glycogen synthase kinase 3 beta/nuclear factor erythroid 2-related factor 2/heme oxygenase-1 signaling pathway

Oxidative stress is the main cause of ischemia/reperfusion injury. Propofol is a commonly used intravenous hypnotic anesthetic agent with antioxidant properties. In this study, we aimed to elucidate the protective effects of propofol on H2O2-induced cardiomyocyte injury and myocardial ischemic/reperfusion injury (MIRI) in rats. Cardiomyocyte injury was evaluated by determining cardiac troponin-1 (cTn-1) and creatine kinase-MB (CK-MB) levels. Antioxidative stress was assessed by measuring lactate dehydrogenase (LDH), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), reactive oxygen species (ROS), and catalase (CAT) levels. Apoptosis was evaluated using flow cytometry and TUNEL assays. Bax and Bcl-2 expression levels were determined by quantitative reverse transcription PCR (qRT-PCR) and Western blotting. The levels of glycogen synthase kinase 3 beta/nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway-related factors were measured using Western blotting. Myocardial infarction in rats was analyzed using an Evans blue staining assay. The results showed that propofol reduced the levels of CK-MB, cTn-1, LDH, MDA, and ROS, and increased the levels of GSH, SOD, and CAT in H2O2-treated H9c2 cells. Additionally, propofol inhibited H2O2-induced apoptosis by downregulating Bax and upregulating Bcl-2. Moreover, propofol decreased the area of myocardial infarction in rats with MIRI. The GSK3β-Nrf2/HO-1 signaling pathway was activated by propofol. Rescue experiments showed that Nrf2 knockdown alleviated the effects of propofol on oxidative stress and apoptosis in H9c2 cells. In conclusion, propofol attenuated H2O2-induced myocardial cell injury by regulating the GSK3β/Nrf2/HO-1 signaling pathway and alleviating MIRI, suggesting that propofol is a promising therapeutic option for ischemic heart disease.

Pinocembrin pretreatment counteracts the chlorpyrifos-induced HO-1 downregulation, mitochondrial dysfunction, and inflammation in the SH-SY5Y cells

Chlorpyrifos (CPF), an insecticide, induces pro-oxidant, pro-inflammatory, and pro-apoptotic effects in animal cells. Contamination with CPF occurs not only in farms, since CPF is found in the food consumed in homes. Recently, it was demonstrated that CPF affects the mitochondria, inhibiting components of the electron transfer chain (ETC), causing loss of mitochondrial membrane potential (MMP), and reducing the synthesis of adenosine triphosphate (ATP) by the Complex V. Pinocembrin (PB) is found in propolis and exhibits antioxidant, anti-inflammatory, and anti-apoptotic effects in mammalian cells. PB is a potent inducer of the nuclear factor erythroid 2-related factor 2 (Nrf2), which is a major transcription factor controlling the expression of heme oxygease-1 (HO-1), among others. In the present work, we investigated whether PB would be able to prevent the mitochondrial and immune dysfunctions in the human neuroblastoma SH-SY5Y cells exposed to CPF. PB was tested at 1-25 µM for 4 h before the administration of CPF at 100 µM for additional 24 h. We found that PB prevented the CPF-induced inhibition of ETC, loss of MMP, and decline in the ATP synthesis. PB also promoted anti-inflammatory actions in this experimental model. Silencing of Nrf2 or inhibition of HO-1 suppressed the PB-induced effects in the CPF-challenged cells. Thus, PB promoted beneficial effects by a mechanism dependent on the Nrf2/HO-1/CO + BR axis in the CPF-treated cells.

A review on the molecular basis underlying the protective effects of Andrographis paniculata and andrographolide against myocardial injury

Andrographolide is the major compound found in the medicinal plant, Andrographis paniculata (Burm.f.) Nees, which accounts for its medicinal properties. Both the plant extract and compound have been reported to exhibit potential cardiovascular activities. This review summarises related studies describing the biological activities and target mechanisms of A. paniculata and andrographolide in vivo and in vitro. The current evidence unambiguously indicated the protective effects provided by A. paniculata and andrographolide administration against myocardial injury. The intervention ameliorates the symptoms of myocardial injury by interfering with the inductive phase of a) inflammatory response mediated by nuclear factor-kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) signalling molecules; b) oxidative stress via activation of nuclear factor erythroid 2-related factor (Nrf-2) and reduction of enzymes responsible for generating reactive oxygen and nitrogen species; c) intrinsic and extrinsic mechanisms in apoptosis regulated by upstream insulin-like growth factor-1 receptor (IGF-1R) and peroxisome proliferator-activated receptor-alpha (PPAR-α); d) profibrotic growth factors thus reducing cardiac fibrosis, improving endothelial function and fibrinolytic function. In conclusion, A. paniculata and andrographolide possess therapeutic potential in the management of myocardial injury, which requires further validation in human clinical trials.