Sulforaphane protects against ethanol-induced oxidative stress and apoptosis in neural crest cells by the induction of Nrf2-mediated antioxidant response

Sulforaphane Attenuates Ethanol-Induced Teratogenesis and Dysangiogenesis in Zebrafish Embryos

Prenatal ethanol exposure can cause a broad range of abnormalities in newborns known as Fetal Alcohol Spectrum Disorder (FASD). Despite significant progress in understanding the disease mechanisms of FASD, there remains a strong global need for effective therapies. To evaluate the therapeutic potential of sulforaphane (SFN), an active compound extracted from cruciferous vegetables, in preventing FASD, ethanol-exposed zebrafish embryos were pretreated, co-treated, or post-treated with various concentrations of SFN. The FASD-like morphological features, survival rate, hatching rate, and vascular development were then assessed in the zebrafish embryos. It was found that pretreatment with 2 μM SFN during 3-24 hpf had no noticeable protective effects against teratogenicity induced by subsequent 1.5% ethanol exposure during 24-48 hpf. In contrast, co-treatment with 2 μM SFN and 1.5% ethanol during 3-24 hpf significantly alleviated a range of ethanol-induced malformations, including reduced body length, small eyes, reduced brain size, small otic vesicle, small jaw, and pericardial edema. Post-treatment with 3 μM SFN for 4 days following 1.5% ethanol exposure during 3-24 hpf also significantly reduced the characteristic features of FASD, decreasing the mortality rate and restoring body length, eye size, brain size, and otic vesicle circumference. Moreover, we found that ethanol, even at a low dose (0.5%), causes vascular development deficit in the zebrafish embryos, which were also largely rescued by SFN treatment. These data indicated that SFN has great potential to be used in the prevention and treatment of FASD.

SESN2-Mediated AKT/GSK-3β/NRF2 Activation to Ameliorate Adriamycin Cardiotoxicity in High-Fat Diet-Induced Obese Mice

Aims: Obese patients are highly sensitive to adriamycin (ADR)-induced cardiotoxicity. However, the potential mechanism of superimposed toxicity remains to be elucidated. Sestrin 2 (SESN2), a potential antioxidant, could attenuate stress-induced cardiomyopathy; therefore, this study aims to explore whether SESN2 enhances cardiac resistance to ADR-induced oxidative damage in high-fat diet (HFD)-induced obese mice. Results: The results revealed that obesity decreased SESN2 expression in ADR-exposed heart. And, HFD mice may predispose to ADR-induced cardiotoxicity, which was probably associated with inhibiting protein kinase B (AKT), glycogen synthase kinase-3 beta (GSK-3β) phosphorylation and subsequently blocking nuclear localization of nuclear factor erythroid-2 related factor 2 (NRF2), ultimately resulting in cardiac oxidative damage. However, these destructive cascades and cardiac oxidative damage effects induced by HFD/sodium palmitate combined with ADR were blocked by overexpression of SESN2. Moreover, the antioxidant effect of SESN2 could be largely abolished by sh-Nrf2 or wortmannin. And sulforaphane, an NRF2 agonist, could remarkably reverse cardiac pathological and functional abnormalities caused by ADR in obese mice. Innovation and Conclusion: This study demonstrated that SESN2 might be a promising therapeutic target for improving anthracycline-related cardiotoxicity in obesity by upregulating activity of NRF2 via AKT/GSK-3β/Src family tyrosine kinase signaling pathway. Antioxid. Redox Signal. 40, 598-615.

Broccoli Improves Lipid Metabolism and Intestinal Flora in Mice with Type 2 Diabetes Induced by HFD and STZ Diet

Globally, type 2 diabetes (T2DM) is on the rise. Maintaining a healthy diet is crucial for both treating and preventing T2DM.As a common vegetable in daily diet, broccoli has antioxidant, anti-inflammatory and anticarcoma physiological activities. We developed a mouse model of type 2 diabetes and carried out a systematic investigation to clarify the function of broccoli in reducing T2DM symptoms and controlling intestinal flora. The findings demonstrated that broccoli could successfully lower fasting blood glucose (FBG), lessen insulin resistance, regulate lipid metabolism, lower the levels of TC, TG, LDL-C, and MDA, stop the expression of IL-1β and IL-6, and decrease the harm that diabetes causes to the pancreas, liver, fat, and other organs and tissues. Furthermore, broccoli altered the intestinal flora's makeup in mice with T2DM. At the genus level, the relative abundance of Allobaculum decreased, and that of Odoribacter and Oscillospira increased; At the family level, the relative abundances of Odoribacteraceae, Rikenellaceae and S24-7 decreased, while the relative abundances of Erysipelotrichaceae and Rikenellaceae increased.

The key roles of reactive oxygen species in microglial inflammatory activation: Regulation by endogenous antioxidant system and exogenous sulfur-containing compounds

Aberrant innate immunity in the brain has been implicated in the pathogenesis of several central nervous system (CNS) disorders, including Alzheimer's disease, Huntington's disease, Parkinson's disease, stroke, amyotrophic lateral sclerosis, and depression. Except for extraparenchymal CNS-associated macrophages, which predominantly afford protection against peripheral invading pathogens, it has been reported that microglia, a population of macrophage-like cells governing CNS immune defense in nearly all neurological diseases, are the main CNS resident immune cells. Although microglia have been recognized as the most important source of reactive oxygen species (ROS) in the CNS, ROS also may underlie microglial functions, especially M1 polarization, by modulating redox-sensitive signaling pathways. Recently, endogenous antioxidant systems, including glutathione, hydrogen sulfide, superoxide dismutase, and methionine sulfoxide reductase A, were found to be involved in regulating microglia-mediated neuroinflammation. A series of natural sulfur-containing compounds, including S-adenosyl methionine, S-methyl-L-cysteine, sulforaphane, DMS, and S-alk(enyl)-l-cysteine sulfoxide, modulating endogenous antioxidant systems have been discovered. We have summarized the current knowledge on the involvement of endogenous antioxidant systems in regulating microglial inflammatory activation and the effects of sulfur-containing compounds on endogenous antioxidant systems. Finally, we discuss the possibilities associated with compounds targeting the endogenous antioxidant system to treat neuroinflammation-associated diseases.

Exosome-shuttled miR-126 mediates ethanol-induced disruption of neural crest cell-placode cell interaction by targeting SDF1

During embryonic development, 2 populations of multipotent stem cells, cranial neural crest cells (NCCs) and epibranchial placode cells (PCs), are anatomically adjacent to each other. The coordinated migration of NCCs and PCs plays a major role in the morphogenesis of craniofacial skeletons and cranial nerves. It is known that ethanol-induced dysfunction of NCCs and PCs is a key contributor to the defects of craniofacial skeletons and cranial nerves implicated in fetal alcohol spectrum disorder (FASD). However, how ethanol disrupts the coordinated interaction between NCCs and PCs was not elucidated. To fill in this gap, we established a well-designed cell coculture system to investigate the reciprocal interaction between human NCCs (hNCCs) and human PCs (hPCs), and also monitored the migration behavior of NCCs and PCs in zebrafish embryos. We found that ethanol exposure resulted in a disruption of coordinated hNCCs-hPCs interaction, as well as in zebrafish embryos. Treating hNCCs-hPCs with exosomes derived from ethanol-exposed hNCCs (ExoEtOH) mimicked ethanol-induced impairment of hNCCs-hPCs interaction. We also observed that SDF1, a chemoattractant, was downregulated in ethanol-treated hPCs and zebrafish embryos. Meanwhile, miR-126 level in ExoEtOH was significantly higher than that in control exosomes (ExoCon). We further validated that ExoEtOH-encapsulated miR-126 from hNCCs can be transferred to hPCs to suppress SDF1 expression in hPCs. Knockdown of SDF1 replicated ethanol-induced abnormalities either in vitro or in zebrafish embryos. On the contrary, overexpression of SDF1 or inhibiting miR-126 strongly rescued ethanol-induced impairment of hNCCs-hPCs interaction and developmental defects.

The protective role of sulforaphane and Homer1a in retinal ischemia-reperfusion injury: Unraveling the neuroprotective interplay

AIMS

Retinal ischemia/reperfusion (I/R) injury is a common pathological basis for various ophthalmic diseases. This study aimed to investigate the potential of sulforaphane (SFN) and Homer1a in regulating cell apoptosis induced by retinal I/R injury and to explore the underlying regulatory mechanism between them.

MATERIALS AND METHODS

In in vivo experiments, C57BL/6J mice and Homer1flox/-/Homer1a+/-/Nestin-Cre+/- mice were used to construct retinal I/R injury models. In vitro experiments utilized the oxygen-glucose deprivation-reperfusion (OGD/R) injury model with primary retinal ganglion cells (RGCs). The effects of Homer1a and SFN on cell apoptosis were observed through pathological analyses, flow cytometry, and visual electrophysiological assessments.

KEY FINDINGS

We discovered that after OGD/R injury, apoptosis of RGCs and intracellular Ca2+ activity significantly increased. However, these changes were reversed upon the addition of SFN, and similar observations were reproduced in in vivo studies. Furthermore, both in vivo and in vitro studies confirmed the upregulation of Homer1a after I/R, which could be further enhanced by the administration of SFN. Moreover, upregulation of Homer1a resulted in a reduction in cell apoptosis and pro-apoptotic proteins, while downregulation of Homer1a had the opposite effect. Flash visual evoked potential, oscillatory potentials, and escape latency measurements in mice supported these findings. Furthermore, the addition of SFN strengthened the neuroprotective effects in the OGD/R + H+ group but weakened them in Homer1flox/-/Homer1a+/-/Nestin-Cre+/- mice.

SIGNIFICANCE

These results indicate that Homer1a plays a significant role in the therapeutic potential of sulforaphane for retinal I/R injury, thereby providing a theoretical basis for clinical treatment.

Neural crest cells and fetal alcohol spectrum disorders: Mechanisms and potential targets for prevention

Fetal alcohol spectrum disorders (FASD) are a group of preventable and nongenetic birth defects caused by prenatal alcohol exposure that can result in a range of cognitive, behavioral, emotional, and functioning deficits, as well as craniofacial dysmorphology and other congenital defects. During embryonic development, neural crest cells (NCCs) play a critical role in giving rise to many cell types in the developing embryos, including those in the peripheral nervous system and craniofacial structures. Ethanol exposure during this critical period can have detrimental effects on NCC induction, migration, differentiation, and survival, leading to a broad range of structural and functional abnormalities observed in individuals with FASD. This review article provides an overview of the current knowledge on the detrimental effects of ethanol on NCC induction, migration, differentiation, and survival. The article also examines the molecular mechanisms involved in ethanol-induced NCC dysfunction, such as oxidative stress, altered gene expression, apoptosis, epigenetic modifications, and other signaling pathways. Furthermore, the review highlights potential therapeutic strategies for preventing or mitigating the detrimental effects of ethanol on NCCs and reducing the risk of FASD. Overall, this article offers a comprehensive overview of the current understanding of the impact of ethanol on NCCs and its role in FASD, shedding light on potential avenues for future research and intervention.

An experimental evaluation of the efficacy of perinatal sulforaphane supplementation to decrease the incidence and severity of vinclozolin-induced hypospadias in the mouse model

Determining the mechanisms of toxicity induced by pollutants has long been a research priority in lieu of considering the mechanisms of resilience that prevent deleterious impacts. Protective mechanisms in many taxa can be therapeutically targeted to enhance resilience to synthetic toxicants. For example, the environmental sensor, Nuclear factor (erythroid-derived 2)-like 2 (Nfe2l2 or Nrf2), a transcription factor, facilitates transcription of many protective genes. Hypospadias is a common malformation of the penis. The risk of being born with hypospadias increases with pollutant exposure. We use vinclozolin-induced hypospadias in the mouse as a model to test the hypothesis that pollutant-induced birth defects can be prevented and reduced in severity by augmenting natural mechanisms of resilience. Pregnant mice were exposed to the demasculinizing toxicant, vinclozolin, in combination with increasing doses of the NRF2 activator, sulforaphane. The sulforaphane dose that most effectively increased masculinization (anogenital distance) was identified and used to test the hypothesis that sulforaphane reduces the hypospadias-inducing potency of vinclozolin. Finally, a Nrf2 knockout study was conducted to test whether NRF2 was required for the sulforaphane-induced rescue effects. Sulforaphane supplementation to vinclozolin exposed embryos increased anogenital distance in a nonlinear fashion typical of Nrf2 activators. The most effective dose of sulforaphane (45 mg/kg) reduced the occurrence and severity of vinclozolin-induced hypospadias and corrected penis morphogenesis. The sulforaphane-induced rescue effect was dependent on the presence of Nrf2. Nrf2 plays a critical role in protecting the fetus from vinclozolin and reduces the incidence and severity of hypospadias, the most common birth defect in boys in many countries. This work lays a foundation for developing prenatal supplements that will protect the fetus from pollutant-induced hypospadias. Studying the protective mechanisms that drive resilience to toxicants will facilitate innovation of protective therapies.

Up-regulation of microRNA-34a mediates ethanol-induced impairment of neural crest cell migration in vitro and in zebrafish embryos through modulating epithelial-mesenchymal transition by targeting Snail1

Prenatal ethanol exposure can impair neural crest cell (NCC) development, including NCC survival, differentiation and migration, contributing to the craniofacial dysmorphology in Fetal Alcohol Spectrum Disorders (FASD). Epithelial-mesenchymal transition (EMT) plays an important role in regulating the migration of NCCs. The objective of this study is to determine whether ethanol exposure can suppress NCC migration through inhibiting EMT and whether microRNA-34a (miR-34a) is involved in the ethanol-induced impairment of EMT in NCCs. We found that exposure to 100 mM ethanol significantly inhibited the migration of NCCs. qRT-PCR and Western Blot analysis revealed that exposure to ethanol robustly reduced the mRNA and protein expression of Snail1, a critical transcriptional factor that has a pivotal role in the regulation of EMT. Ethanol exposure also significantly increased the mRNA expression of the Snail1 target gene E-cadherin1 and inhibited EMT in NCCs. We also found that exposure to ethanol significantly elevated the expression of miR-34a that targets Snail1 in NCCs. In addition, down-regulation of miR-34a prevented ethanol-induced repression of Snail1 and diminished ethanol-induced upregulation of Snail1 target gene E-cadherin1 in NCCs. Inhibition of miR-34a restored EMT and prevented ethanol-induced inhibition of NCC migration in vitro and in zebrafish embryos in vivo. These results demonstrate that ethanol-induced upregulation of miR-34a contributes to the impairment of NCC migration through suppressing EMT by targeting Snail1.

Riboceine Rescues Auranofin-Induced Craniofacial Defects in Zebrafish

Craniofacial abnormalities are a common group of congenital developmental disorders that can require intensive oral surgery as part of their treatment. Neural crest cells (NCCs) contribute to the facial structures; however, they are extremely sensitive to high levels of oxidative stress, which result in craniofacial abnormalities under perturbed developmental environments. The oxidative stress-inducing compound auranofin (AFN) disrupts craniofacial development in wildtype zebrafish embryos. Here, we tested whether the antioxidant Riboceine (RBC) rescues craniofacial defects arising from exposure to AFN. RBC rescued AFN-induced cellular apoptosis and distinct defects of the cranial cartilage in zebrafish larvae. Zebrafish embryos exposed to AFN have higher expression of antioxidant genes gstp1 and prxd1, with RBC treatment partially rescuing these gene expression profiles. Our data suggest that antioxidants may have utility in preventing defects in the craniofacial cartilage owing to environmental or genetic risk, perhaps by enhancing cell survival.

Sulforaphane inhibits the production of Aβ partially through the activation of Nrf2-regulated oxidative stress

Sulforaphane (SFN), a potent nuclear factor erythroid 2-related factor 2 (Nrf2) activator, presents a potential role in improving Alzheimer's disease (AD)-specific symptoms. However, the regulation mechanism of SFN in AD is poorly understood. Here, we established AD models both in vitro and in vivo. Animal behaviors were tested by the Morris water maze test. The pathology of the hippocampus and the content of Aβ were detected. SFN (40 mg kg^-1) decreased the escape latency (24.96 ± 7.43 s) and increased the target-zone frequency (3.19 ± 1.19) in rats. SFN improved the pathological morphology and the number of neurons in the hippocampus. Additionally, SFN significantly upregulated the contents of thioredoxin and glutathione as well as the activities of antioxidant enzymes, along with the expression of the Nrf2 protein. Conversely, SFN lowered the Aβ content and ROS level in N2a/APP cells. After silencing the Nrf2 by SiRNA, the inhibitory effects of SFN on ROS and Aβ production were partially weakened. In conclusion, the improvement of AD by SFN was closely related with Nrf2 activation.

Sulforaphane (SFA) protects neuronal cells from oxygen & glucose deprivation (OGD)

BACKGROUND

Perinatal brain injury results in neurodevelopmental disabilities (neuroDDs) that include cerebral palsy, autism, attention deficit disorder, epilepsy, learning disabilities and others. Commonly, injury occurs when placental circulation, that is responsible for transporting nutrients and oxygen to the fetus, is compromised. Placental insufficiency (PI) is a reduced supply of blood and oxygen to the fetus and results in a hypoxic-ischemic (HI) environment. A significant HI state in-utero leads to perinatal compromise, characterized by fetal growth restriction and brain injury. Given that over 80% of perinatal brain injuries that result in neuroDDs occur during gestation, prior to birth, preventive approaches are needed to reduce or eliminate the potential for injury and subsequent neuroDDs. Sulforaphane (SFA) derived from cruciferous vegetables such as broccoli sprouts (BrSps) is a phase-II enzyme inducer that acts via cytoplasmic Nrf2 to enhance the production of anti-oxidants in the brain through the glutathione pathway. We have previously shown a profound in vivo neuro-protective effect of BrSps/SFA as a dietary supplement in pregnant rat models of both PI and fetal inflammation. Strong evidence also points to a role for SFA as treatment for various cancers. Paradoxically, then SFA has the ability to enhance cell survival, and with conditions of cancer, enhance cell death. Given our findings of the benefit of SFA/Broccoli Sprouts as a dietary supplement during pregnancy, with improvement to the fetus, it is important to determine the beneficial and toxic dosing range of SFA. We therefore explored, in vitro, the dosing range of SFA for neuronal and glial protection and toxicity in normal and oxygen/glucose deprived (OGD) cell cultures.

METHODS

OGD simulates, in vitro, the condition experienced by the fetal brain due to PI. We developed a cell culture model of primary cortical neuronal, astrocyte and combined brain cell co-cultures from newborn rodent brains. The cultures were exposed to an OGD environment for various durations of time to determine the LD50 (duration of OGD required for 50% cell death). Using the LD50 as the time point, we evaluated the efficacy of varying doses of SFA for neuroprotective and neurotoxicity effects. Control cultures were exposed to normal media without OGD, and cytotoxicity of varying doses of SFA was also evaluated. Immunofluorescence (IF) and Western blot analysis of cell specific markers were used for culture characterization, and quantification of LD50. Efficacy and toxicity effect of SFA was assessed by IF/high content microscopy and by AlamarBlue viability assay, respectively.

RESULTS

We determined the LD50 to be 2 hours for neurons, 8 hours for astrocytes, and 10 hours for co-cultures. The protective effect of SFA was noticeable at 2.5 μM and 5 μM for neurons, although it was not significant. There was a significant protective effect of SFA at 2.5 μM (p<0.05) for astrocytes and co-cultures. Significant toxicity ranges were also confirmed in OGD cultures as ≥ 100 μM (p<0.05) for astrocytes, ≥ 50 μM (p<0.01) for co-cultures, but not toxic in neurons; and toxic in control cultures as ≥ 100 μM (p<0.01) for neurons, and ≥ 50 μM (p<0.01) for astrocytes and co-cultures. One Way ANOVA and Dunnett's Multiple Comparison Test were used for statistical analysis.

CONCLUSIONS

Our results indicate that cell death shows a trend to reduction in neuronal and astrocyte cultures, and is significantly reduced in co-cultures treated with low doses of SFA exposed to OGD. Doses of SFA that were 10 times higher were toxic, not only under conditions of OGD, but in normal control cultures as well. The findings suggest that: 1. SFA shows promise as a preventative agent for fetal ischemic brain injury, and 2. Because the fetus is a rapidly growing organism with profound cell multiplication, dosing parameters must be established to insure safety within efficacious ranges. This study will influence the development of innovative therapies for the prevention of childhood neuroDD.

Sulforaphane Protects Against Ethanol-Induced Apoptosis in Human Neural Crest Cells Through Diminishing Ethanol-Induced Hypermethylation at the Promoters of the Genes Encoding the Inhibitor of Apoptosis Proteins

The neural crest cell (NCC) is a multipotent progenitor cell population that is sensitive to ethanol and is implicated in the Fetal Alcohol Spectrum Disorders (FASD). Studies have shown that sulforaphane (SFN) can prevent ethanol-induced apoptosis in NCCs. This study aims to investigate whether ethanol exposure can induce apoptosis in human NCCs (hNCCs) through epigenetically suppressing the expression of anti-apoptotic genes and whether SFN can restore the expression of anti-apoptotic genes and prevent apoptosis in ethanol-exposed hNCCs. We found that ethanol exposure resulted in a significant increase in the expression of DNMT3a and the activity of DNMTs. SFN treatment diminished the ethanol-induced upregulation of DNMT3a and dramatically reduced the activity of DNMTs in ethanol-exposed hNCCs. We also found that ethanol exposure induced hypermethylation at the promoter regions of two inhibitor of apoptosis proteins (IAP), NAIP and XIAP, in hNCCs, which were prevented by co-treatment with SFN. SFN treatment also significantly diminished ethanol-induced downregulation of NAIP and XIAP in hNCCs. The knockdown of DNMT3a significantly enhanced the effects of SFN on preventing the ethanol-induced repression of NAIP and XIAP and apoptosis in hNCCs. These results demonstrate that SFN can prevent ethanol-induced apoptosis in hNCCs by preventing ethanol-induced hypermethylation at the promoter regions of the genes encoding the IAP proteins and diminishing ethanol-induced repression of NAIP and XIAP through modulating DNMT3a expression and DNMT activity.

An Insight into Molecular Mechanisms and Novel Therapeutic Approaches in Epileptogenesis

Epilepsy is the second most common neurological disease with abnormal neural activity involving the activation of various intracellular signalling transduction mechanisms. The molecular and system biology mechanisms responsible for epileptogenesis are not well defined or understood. Neuroinflammation, neurodegeneration and Epigenetic modification elicit epileptogenesis. The excessive neuronal activities in the brain are associated with neurochemical changes underlying the deleterious consequences of excitotoxicity. The prolonged repetitive excessive neuronal activities extended to brain tissue injury by the activation of microglia regulating abnormal neuroglia remodelling and monocyte infiltration in response to brain lesions inducing axonal sprouting contributing to neurodegeneration. The alteration of various downstream transduction pathways resulted in intracellular stress responses associating endoplasmic reticulum, mitochondrial and lysosomal dysfunction, activation of nucleases, proteases mediated neuronal death. The recently novel pharmacological agents modulate various receptors like mTOR, COX-2, TRK, JAK-STAT, epigenetic modulators and neurosteroids are used for attenuation of epileptogenesis. Whereas the various molecular changes like the mutation of the cell surface, nuclear receptor and ion channels focusing on repetitive episodic seizures have been explored by preclinical and clinical studies. Despite effective pharmacotherapy for epilepsy, the inadequate understanding of precise mechanisms, drug resistance and therapeutic failure are the current fundamental problems in epilepsy. Therefore, the novel pharmacological approaches evaluated for efficacy on experimental models of epilepsy need to be identified and validated. In addition, we need to understand the downstream signalling pathways of new targets for the treatment of epilepsy. This review emphasizes on the current state of novel molecular targets as therapeutic approaches and future directions for the management of epileptogenesis. Novel pharmacological approaches and clinical exploration are essential to make new frontiers in curing epilepsy.

The phytoprotective agent sulforaphane prevents inflammatory degenerative diseases and age-related pathologies via Nrf2-mediated hormesis

In numerous experimental models, sulforaphane (SFN) is shown herein to induce hormetic dose responses that are not only common but display endpoints of biomedical and clinical relevance. These hormetic responses are mediated via the activation of nuclear factor erythroid- derived 2 (Nrf2) antioxidant response elements (AREs) and, as such, are characteristically biphasic, well integrated, concentration/dose dependent, and specific with regard to the targeted cell type and the temporal profile of response. In experimental disease models, the SFN-induced hormetic activation of Nrf2 was shown to effectively reduce the occurrence and severity of a wide range of human-related pathologies, including Parkinson's disease, Alzheimer's disease, stroke, age-related ocular damage, chemically induced brain damage, and renal nephropathy, amongst others, while also enhancing stem cell proliferation. Although SFN was broadly chemoprotective within an hormetic dose-response context, it also enhanced cell proliferation/cell viability at low concentrations in multiple tumor cell lines. Although the implications of the findings in tumor cells are largely uncertain at this time and warrant further consideration, the potential utility of SFN in cancer treatment has not been precluded. This assessment of SFN complements recent reports of similar hormesis-based chemoprotections by other widely used dietary supplements, such as curcumin, ginkgo biloba, ginseng, green tea, and resveratrol. Interestingly, the mechanistic profile of SFN is similar to that of numerous other hormetic agents, indicating that activation of the Nrf2/ARE pathway is probably a central, integrative, and underlying mechanism of hormesis itself. The Nrf2/ARE pathway provides an explanation for how large numbers of agents that both display hormetic dose responses and activate Nrf2 can function to limit age-related damage, the progression of numerous disease processes, and chemical- and radiation- induced toxicities. These findings extend the generality of the hormetic dose response to include SFN and many other chemical activators of Nrf2 that are cited in the biomedical literature and therefore have potentially important public health and clinical implications.

MicroRNA-135a Protects Against Ethanol-Induced Apoptosis in Neural Crest Cells and Craniofacial Defects in Zebrafish by Modulating the Siah1/p38/p53 Pathway

MicroRNAs (miRNAs) are small non-coding RNAs that are involved in various biological processes, including apoptosis, by regulating gene expression. This study was designed to test the hypothesis that ethanol-induced downregulation of miR-135a contributes to ethanol-induced apoptosis in neural crest cells (NCCs) by upregulating Siah1 and activating the p38 mitogen-activated protein kinase (MAPK)/p53 pathway. We found that treatment with ethanol resulted in a significant decrease in miR-135a expression in both NCCs and zebrafish embryos. Ethanol-induced downregulation of miR-135a resulted in the upregulation of Siah1 and the activation of the p38 MAPK/p53 pathway and increased apoptosis in NCCs and zebrafish embryos. Ethanol exposure also resulted in growth retardation and developmental defects that are characteristic of fetal alcohol spectrum disorders (FASD) in zebrafish. Overexpression of miRNA-135a significantly reduced ethanol-induced upregulation of Siah1 and the activation of the p38 MAPK/p53 pathway and decreased ethanol-induced apoptosis in NCCs and zebrafish embryos. In addition, ethanol-induced growth retardation and craniofacial defects in zebrafish larvae were dramatically diminished by the microinjection of miRNA-135a mimics. These results demonstrated that ethanol-induced downregulation of miR-135a contributes to ethanol-induced apoptosis in NCCs by upregulating Siah1 and activating the p38 MAPK/p53 pathway and that the overexpression of miRNA-135a can protect against ethanol-induced apoptosis in NCCs and craniofacial defects in a zebrafish model of FASD.

Sulforaphane alleviates ethanol-mediated central inhibition and reverses chronic stress-induced aggravation of acute alcoholism via targeting Nrf2-regulated catalase expression

Acute ethanol intoxication by excessive drinking is an important cause of alcohol-induced death. Stress exposure has been identified as one risk factor for alcohol abuse. Previous reports indicated that stressors may augment inhibitory effects of alcohol, but the underlying mechanism remains unknown. Here, we reported that chronic unpredictable stress increased the sensitivity to the acute ethanol intoxication in mice via impairing nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-catalase signaling. Nrf2 activity regulates the expression of catalase, a key antioxidant enzyme that mediates ethanol oxidation in the brain. Pharmacological blockade of catalase or Nrf2 activity significantly aggravated acute ethanol intoxication. Sulforaphane, a cruciferous vegetable-derived activator of Nrf2, significantly attenuated acute ethanol intoxication. Furthermore, the stress-induced aggravation of acute alcoholism was rapidly reversed by sulforaphane. Our findings suggest that Nrf2 may function as a novel drug target for the prevention of acute alcoholism, especially in psychiatric patients, by controlling catalase-mediated ethanol oxidation.

Protective Effects of Sulforaphane on Exercise-Induced Organ Damage via Inducing Antioxidant Defense Responses

Regular exercise is beneficial to maintain a healthy lifestyle, but the beneficial effects are lost in the case of acute exhaustive exercise; this causes significant inflammation, oxidative stress along with organ damage. Recently, sulforaphane (SFN), an indirect antioxidant, has drawn special attention for its potential protective effect against inflammation and oxidative stress. However, no studies have been performed regarding acute exhaustive exercise-induced organ damage in association with SFN administration. Therefore, the aim of this study was to investigate the effects of SFN on acute exhaustive exercise-induced organ damage and the mechanisms involved. To perform the study, we divided mice into four groups: Control, SFN, exercise, and SFN plus exercise. The SFN group was administered orally (50 mg/kg body wt) 2 h before the running test. We measured plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH), and acute exhaustive exercise significantly increased these biomarkers. In addition, the mRNA expression of pro-inflammatory cytokines, IL-6, IL-1β, and TNF-α, were significantly increased in the liver of exercise group. However, the SFN plus exercise group showed a significant reduction in the expression of cytokines and blood biomarkers of tissue damage or cell death. Furthermore, we measured mRNA expression of Nrf2, heme oxygenase (HO)-1, and antioxidant defense enzymes expression, i.e., superoxide dismutase (SOD1), catalase (CAT), and glutathione peroxidase (GPx1) in the liver. The expression of all these biomarkers was significantly upregulated in the SFN plus exercise group. Collectively, SFN may protect the liver from exhaustive exercise-induced inflammation via inducing antioxidant defense response through the activation of Nrf2/HO-1 signal transduction pathway.

Polysaccharide from Echinacea purpurea reduce the oxidant stress in vitro and in vivo

Echinacea purpurea polysaccharides (EPPS) were extracted through water extract and alcohol precipitate method. Three polysaccharides were purified by DEAE cellulose, named EPPS-1, EPPS-2 and EPPS-3. The antioxidant activities in three polysaccharides were screened by free radical scavenging test and EPPS-3 possessed the best antioxidant function. Then the antioxidant activities of EPPS-3 were further explored in oxidative damage model in vitro and in vivo for the first time. The results showed that the antioxidases and the metabolism content were significantly improved in EPPS-3 group. EPPS-3 could protect hepatic tissue from the injury of CCl₄ compared with the oxidative damage model. The mechanism research demonstrated that EPPS-3 restrained cell apoptosis and promoted Nrf2 cell signal pathway to play an antioxidant impact. Therefore, EPPS-3 an ingredient could be served as amazing gift for food industry and feed additive.

Sulforaphane protects against ethanol-induced apoptosis in neural crest cells through restoring epithelial-mesenchymal transition by epigenetically modulating the expression of Snail1

Ethanol-induced apoptosis in neural crest cells (NCCs), a multipotent progenitor cell population, is implicated in the Fetal Alcohol Spectrum Disorders (FASD). Studies have demonstrated that sulforaphane (SFN) can prevent ethanol-induced apoptosis in NCCs. The objective of this study is to investigate whether ethanol exposure can induce apoptosis in NCCs by inhibiting epithelial-mesenchymal transition (EMT) and whether SFN can prevent ethanol-induced apoptosis by epigenetically modulating the expression of Snail1, a key transcriptional factor that promotes EMT. We found that ethanol exposure resulted in a significant increase in apoptosis in NCCs. Co-treatment with SFN significantly reduced ethanol-induced apoptosis. Treatment with SFN also dramatically diminished ethanol-induced changes in the expression of E-cadherin and vimentin, and restored EMT in ethanol-exposed NCCs. In addition, ethanol exposure reduced the levels of trimethylation of histone H3 lysine 4 (H3K4me3) at the promoters of Snail1. SFN treatment diminished the ethanol-induced reduction of H3K4me3 at the promoter regions of the Snail1 gene, restored the expression of Snail1 and down-regulated Snail1 target gene E-cadherin. Knockdown of Snail1 significantly reduced the protective effects of SFN on ethanol-induced apoptosis. These results demonstrate that SFN can protect against ethanol-induced apoptosis by preventing ethanol-induced reduction in the levels of H3K4me3 at the promoters of Snail1, restoring the expression of Snail1 and EMT in ethanol-exposed NCCs.

Synergistic chemopreventive effect of allyl isothiocyanate and sulforaphane on non-small cell lung carcinoma cells

Isothiocyanates from cruciferous vegetables are known for their potential anti-carcinogenic activities. These isothiocyanates are frequently consumed together as part of a regular diet, but their combined effects on carcinogenesis have not been well studied. Herein, we tested the hypothesis that combination of two isothiocyanates, i.e. allyl isothiocyanate and sulforaphane, produced a synergy in inhibiting the growth of A549 lung cancer cells. Our results showed that the combination treatment led to a stronger growth inhibition than the singular treatment. Isobologram analysis proved that the enhanced inhibitory effect of the combination treatment was synergistic. Flow cytometry demonstrated that the combination treatment caused more extensive cell cycle arrest and apoptosis than the singular treatment with modified expression of key proteins regulating these cellular processes. The combined treatment resulted in the production of intracellular reactive oxygen species, which might contribute to the inhibitory effects on cancer cells. Moreover, a synergy between allyl isothiocyanate and sulforaphane was also observed in anti-cell migration. Collectively, our results have demonstrated the potential of different isothiocyanates used in combination to produce enhanced protective effects against carcinogenesis.

MicroRNA-34a mediates ethanol-induced impairment of neural differentiation of neural crest cells by targeting autophagy-related gene 9a

Neural crest cells (NCCs) are multipotent progenitor cells that are sensitive to ethanol and are implicated in Fetal Alcohol Spectrum Disorders (FASD). The objective of this study is to test whether ethanol exposure can inhibit the neural differentiation of NCCs by inhibiting autophagy and whether miR-34a is involved in ethanol-induced inhibition of autophagy in NCCs. We found that ethanol exposure resulted in the inhibition of neural differentiation of NCCs. Exposure to ethanol also significantly decreased autophagy in NCCs, as indicated by a decreased LC3II/I ratio and an elevated expression of p62 protein. Knockdown of p62 restored the expression of the neurogenesis genes, NF and Mash1, in ethanol-exposed NCCs, suggesting that ethanol exposure can inhibit the neural differentiation of NCCs by inhibiting autophagy. We also found that ethanol exposure resulted in a significant increase in miR-34a expression in NCCs. Inhibition of miR-34a restored the expression of Atg9a, a direct target of miR-34a and significantly decreased ethanol-induced inhibition of autophagy in NCCs. Down-regulation of miR-34a also prevented ethanol-induced inhibition of neural differentiation of NCCs. These results demonstrate that ethanol-induced inhibition of neural differentiation of NCCs is mediated by the miR-34a through targeting Atg9a.

Cytoprotective Effect of Ligustrum robustum Polyphenol Extract against Hydrogen Peroxide-Induced Oxidative Stress via Nrf2 Signaling Pathway in Caco-2 Cells

Ligustrum robustum is a traditional herbal tea that is widely distributed in southwest China. The health effects of L. robustum are characteristics of clearing heat, antioxidant, inducing resurgence, and improving digestion. However, the molecular mechanisms related to these effects, particularly the antioxidant mechanism, have been seldom reported. The objective of this study was to assess antioxidative capacity of L. robustum, and its protective effects and mechanisms against hydrogen peroxide (H₂O₂) - induced toxicity in Caco-2 cells. Total phenolic contents, free radical scavenging activity, and reducing capacity of L. robustum were measured. The effects of L. robustum on the cell viability and antioxidant defense system were explored. The expression of nuclear factor E2 related factor 2 (Nrf2) and antioxidant genes: quinone oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), and glutamate cysteine ligase (GCL) were analyzed by western blot and qPCR. Pretreatment of L. robustum could significantly reduce H₂O₂-induced toxicity, decrease the level of reactive oxygen species (ROS) and malondialdehyde (MDA), and increase the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione reductase (GR). By activating the expression of Nrf2 and antioxidant genes (NQO1, HO-1, and GCL), L. robustum exerts cytoprotective effect in Caco-2 cells dealt with H₂O₂. Therefore, the well-established model of Caco-2 cells demonstrates that L. robustum may modulate the cytoprotective effect against the H₂O₂-induced oxidative stress through the Nrf2 signaling pathway.

Effects of ethanol on human periodontal ligament fibroblasts subjected to static compressive force

Consumption of toxic substances such as alcohol is widespread in the general population and thus also in patients receiving orthodontic treatment. Since human periodontal ligament (hPDL) fibroblasts play a key role in orthodontic tooth movement (OTM) by expressing cytokines and chemokines, we wanted to clarify whether ethanol modulates the physiological activity and expression pattern of hPDL fibroblasts during static compressive force application. We pre-incubated hPDL fibroblasts for 24 h with different ethanol concentrations, corresponding to casual (0.041% blood alcohol concentration [BAC], % by volume) and excessive (0.179%) alcohol consumption. At each ethanol concentration, we incubated the cells for another 48 h with and without an additional physiological compressive force of 2 g/cm² occurring during orthodontic tooth movement in compression areas of the periodontal ligament. Thereafter, we analyzed expression and secretion of genes and proteins involved in OTM regulation by RT-qPCR and ELISA. We also performed co-culture experiments to observe hPDL-fibroblast-mediated osteoclastogenesis. We observed no effects of ethanol on cytotoxicity or cell viability of hPDL fibroblasts in the applied concentrations. Ethanol showed an enhancing effect on angiogenesis and activity of alkaline phosphatase. Simultaneously, ethanol reduced the induction of IL-6 and increased prostaglandin E₂ synthesis as well as hPDL-fibroblast-mediated osteoclastogenesis without affecting the RANK-L/OPG-system. hPDL fibroblasts thus seem to be a cell type quite resistant to ethanol, as no cytotoxic effects or influence on cell viability were detected. High ethanol concentrations, however, seem to promote bone formation and angiogenesis. Ethanol at 0.179% also enhanced hPDL-induced osteoclastogenesis, indicating increased bone resorption and thus tooth movement velocity to be expected during orthodontic therapy.

Curcumin induces p53-independent inactivation of Nrf2 during oxidative stress-induced apoptosis

The transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) is a master regulator of a battery of antioxidant and detoxificant genes with cytoprotective function. Since Nrf2 inactivation is necessary for the complete execution of apoptosis in the presence of extensive cellular damage caused by oxidative stress, constant activation of Nrf2 may protect tumoral cells from apoptosis. The tumor suppressor gene p53 has been suggested to participate in apoptosis-related repression of Nrf2. Thus, we studied the inactivation of Nrf2 during oxidant-induced apoptosis in a p53 dysfunctional cellular model. Using curcumin dose-response assay and time-response assay in an immortalized lymphoblastoid cell line (control line 45), we observed a time-dependent increase in apoptotic markers such as deoxyribonucleic acid (DNA) fragmentation, phosphatidylserine exposure, and caspase-3, caspase-9 and poly (ADP-ribose) polymerases (PARP) cleavage. Interestingly, at early times of exposure to a proapoptotic dose of curcumin (15 μM), we observed nuclear accumulation of Nrf2 and the expression of Nrf2 target genes, whereas at late exposure times we found a reduction of total and nuclear protein levels of Nrf2 as well as downregulation of Nrf2 target genes in the absence of p53 activation. These data suggest that apoptosis-related inactivation of Nrf2 could occur in a p53 dysfunctional background, opening the possible occurrence of p53-independent mechanism to explain Nrf2 inactivation during apoptosis.

Sulforaphane from Cruciferous Vegetables: Recent Advances to Improve Glioblastoma Treatment

Sulforaphane (SFN), an isothiocyanate (ITC) derived from cruciferous vegetables, particularly broccoli and broccoli sprouts, has been widely investigated due to its promising health-promoting properties in disease, and low toxicity in normal tissue. Although not yet fully understood, many mechanisms of anticancer activity at each step of cancer development have been attributed to this ITC. Given the promising data available regarding SFN, this review aimed to provide an overview on the potential activities of SFN related to the cellular mechanisms involved in glioblastoma (GBM) progression. GBM is the most frequent malignant brain tumor among adults and is currently an incurable disease due mostly to its highly invasive phenotype, and the poor efficacy of the available therapies. Despite all efforts, the median overall survival of GBM patients remains approximately 1.5 years under therapy. Therefore, there is an urgent need to provide support for translating the progress in understanding the molecular background of GBM into more complex, but promising therapeutic strategies, in which SFN may find a leading role.

Sulforaphane Rescues Ethanol-Suppressed Angiogenesis through Oxidative and Endoplasmic Reticulum Stress in Chick Embryos

Our previous study showed that ethanol exposure inhibited embryonic angiogenesis mainly due to the excessive stimulation of reactive oxygen species (ROS) production. In this study, we investigated whether sulforaphane (SFN), a known dietary bioactive compound, could ameliorate ethanol-suppressed angiogenesis using chick embryo angiogenesis models. Using chick yolk sac membrane (YSM) and chorioallantoic membrane (CAM) models, we demonstrated that administration of low concentrations of SFN (2.5-10 μM) alone increased angiogenesis, but high concentrations of SFN (20-40 μM) inhibited angiogenesis. SFN administration alleviated ethanol-suppressed angiogenesis and angiogenesis-related gene expression in both angiogenesis models. Ethanol exposure caused cell apoptosis in chick CAM, and the cell apoptosis could be remitted by administration of SFN. Subsequently, we demonstrated that the ethanol-induced increase in production of ROS and reduction of antioxidant enzymes' activity were partially rescued by SFN. Similar results were obtained in endoplasmic reticulum (ER) stress determination, indicated by ATF6 and GRP78 expression or thapsigargin-induced ER stress in the presence or absence of SFN. Taken together, our experiments show that SFN administration can ameliorate ethanol-suppressed embryonic angiogenesis, and this is mainly achieved by alleviating excessive ROS production and ER stress. This study suggests that SFN, in appropriate concentrations, could be a potential candidate compound for preventing the negative impact of alcohol on angiogenesis.

Sulforaphane restores acetyl-histone H3 binding to Bcl-2 promoter and prevents apoptosis in ethanol-exposed neural crest cells and mouse embryos

Sulforaphane (SFN) is an isothiocyanate derived from cruciferous vegetables. SFN's cytoprotective properties have been demonstrated in several models associated with a variety of disorders. Our recent studies have shown that SFN protects against ethanol-induced oxidative stress and apoptosis in neural crest cells (NCCs), an ethanol-sensitive cell population implicated in Fetal Alcohol Spectrum Disorders (FASD). This study is designed to test the hypothesis that SFN can prevent ethanol-induced apoptosis in NCCs by inhibiting HDAC and increasing histone acetylation at the Bcl-2 promoter. We found that exposure to 50mM ethanol resulted in a significant increase in HDAC activities in NCCs. Treatment with SFN decreased the activities of HDAC in ethanol-exposed NCCs. We also found that SFN treatment significantly increased the expression of acetyl-histone H3 in NCCs treated with ethanol. ChIP-qPCR assay revealed that ethanol exposure significantly decreased acetyl-histone H3 binding to the Bcl-2 promoter while supplementing with SFN reversed the ethanol-induced reduction in acetyl-histone H3 binding to the Bcl-2 promoter. In addition, SFN treatment restored the expression of Bcl-2 in ethanol-exposed NCCs and diminished ethanol-induced apoptosis in NCCs. Treatment with SFN also significantly diminished apoptosis in mouse embryos exposed to ethanol in vivo. These results demonstrate that SFN can epigenetically restore the expression of Bcl-2 and attenuate ethanol-induced apoptosis by increasing histone acetylation at the Bcl-2 promoter and suggest that SFN may prevent FASD through epigenetic regulation of the expression of anti-apoptotic genes.

Supplementation with the Methyl Donor Betaine Prevents Congenital Defects Induced by Prenatal Alcohol Exposure

BACKGROUND

Despite decades of public education about dire consequences of prenatal alcohol exposure (PAE), drinking alcohol during pregnancy remains prevalent. As high as 40% of live-born infants exposed to alcohol during gestation and diagnosed with fetal alcohol syndrome have congenital heart defects that can be life-threatening. In animal models, the methyl donor betaine, found in foods such as wheat bran, quinoa, beets, and spinach, ameliorated neurobehavioral deficits associated with PAE, but effects on heart development are unknown.

METHODS

Previously, we modeled a binge drinking episode during the first trimester in avian embryos. Here, we investigated whether betaine could prevent adverse effects of alcohol on heart development. Embryos exposed to ethanol (EtOH) with and without an optimal dose of betaine (5 μM) were analyzed at late developmental stages. Cardiac morphology parameters were rapidly analyzed and quantified using optical coherence tomography. DNA methylation at early stages was detected by immunofluorescent staining for 5-methylcytosine in sections of embryos treated with EtOH or cotreated with betaine.

RESULTS

Compared to EtOH-exposed embryos, betaine-supplemented embryos had higher late-stage survival rates and fewer gross head and body defects than seen after alcohol exposure alone. Betaine also reduced the incidence of late-stage cardiac defects such as absent vessels, abnormal atrioventricular (AV) valves, and hypertrophic ventricles. Furthermore, betaine cotreatment brought measurements of great vessel diameters, interventricular septum thickness, and AV leaflet volumes in betaine-supplemented embryos close to control values. Early-stage 5-methycytosine staining revealed that DNA methylation levels were reduced by EtOH exposure and normalized by co-administration with betaine.

CONCLUSIONS

This is the first study demonstrating efficacy of the methyl donor betaine in alleviating cardiac defects associated with PAE. These findings highlight the therapeutic potential of low-concentration betaine doses in mitigating PAE-induced birth defects and have implications for prenatal nutrition policies, especially for women who may not be responsive to folate supplementation.

Modulatory Mechanism of Polyphenols and Nrf2 Signaling Pathway in LPS Challenged Pregnancy Disorders

Early embryonic loss and adverse birth outcomes are the major reproductive disorders that affect both human and animals. The LPS induces inflammation by interacting with robust cellular mechanism which was considered as a plethora of numerous reproductive disorders such as fetal resorption, preterm birth, teratogenicity, intrauterine growth restriction, abortion, neural tube defects, fetal demise, and skeletal development retardation. LPS-triggered overproduction of free radicals leads to oxidative stress which mediates inflammation via stimulation of NF-κB and PPARγ transcription factors. Flavonoids, which exist in copious amounts in nature, possess a wide array of functions; their supplementation during pregnancy activates Nrf2 signaling pathway which encounters pregnancy disorders. It was further presumed that the development of strong antioxidant uterine environment during gestation can alleviate diseases which appear at adult stages. The purpose of this review is to focus on modulatory properties of flavonoids on oxidative stress-mediated pregnancy insult and abnormal outcomes and role of Nrf2 activation in pregnancy disorders. These findings would be helpful for providing new insights in ameliorating oxidative stress-induced pregnancy disorders.

AAV-Nrf2 Promotes Protection and Recovery in Animal Models of Oxidative Stress

NRF2 is a transcription factor that drives antioxidant gene expression in multiple organ systems. We hypothesized that Nrf2 overexpression could be therapeutically applied toward diseases in which redox homeostasis is disrupted. In this study, adeno-associated virus (AAV)-Nrf2 was tested in a mouse model of acute acetaminophen-induced liver toxicity and successfully conferred protection from hepatotoxicity, validating the vector design and early onset of NRF2-mediated protection. Furthermore, therapeutic potential of AAV-Nrf2 in chronic disease also was tested in a light-induced mouse model of age-related macular degeneration. Adult BALB/c mice were intravitreally injected with AAV-Nrf2 and subject to light damage following injection. Retinal thickness and function were monitored following light damage using optical coherence tomography and electroretinography, respectively. By 3 months post-damage, injected eyes had greater retinal thickness compared to uninjected controls. At 1 month post-damage, AAV-Nrf2 injection facilitated full functional recovery from light damage. Our results suggest a therapeutic potential for Nrf2 overexpression in acute and long-term capacities in multiple organ systems, opening up doors for combination gene therapy where replacement gene therapy requires additional therapeutic support to prevent further degeneration.

Beneficial Effects of Sulforaphane Treatment in Alzheimer's Disease May Be Mediated through Reduced HDAC1/3 and Increased P75NTR Expression

Alzheimer's disease is an irreversible, progressive neurodegenerative disorder. The accumulation of Aβ in the brain is thought to play a causative role in the development of cognitive dysfunction in Alzheimer's disease. The p75 neurotrophin receptor is of great importance to protect against the Aβ burden and its expression is regulated by histone acetylation. This study investigated whether the phytochemical sulforaphane, a pan-histone deacetylase inhibitor, up-regulates the p75 neurotrophin receptor expression via affecting histone acetylation in protection against Alzheimer's disease. We found that sulforaphane ameliorated behavioral cognitive impairments and attenuated brain Aβ burden in Alzheimer's disease model mice. Additionally, sulforaphane reduced the expression of histone deacetylase1, 2, and 3, up-regulated p75 neurotrophin receptor, and increased levels of acetylated histone 3 lysine 9 and acetylated histone 4 lysine 12 in the cerebral cortex of Alzheimer's disease model mice as well as in Aβ-exposed SH-SY5Y cells. Furthermore, silencing of histone deacetylase1 and 3, but not histone deacetylase2, gene expression with small interfering RNA caused up-regulation of p75 neurotrophin receptor in SH-SY5Y cells. In conclusion, this study demonstrates that sulforaphane can ameliorate neurobehavioral deficits and reduce the Aβ burden in Alzheimer's disease model mice, and the mechanism underlying these effects may be associated with up-regulation of p75 neurotrophin receptor mediated, apparently at least in part, via reducing the expression of histone deacetylase1 and 3.

Hepatoprotective Effects of Antrodia cinnamomea: The Modulation of Oxidative Stress Signaling in a Mouse Model of Alcohol-Induced Acute Liver Injury

In the present study, the components of A. cinnamomea (AC) mycelia were systematically analyzed. Subsequently, its hepatoprotective effects and the underlying mechanisms were explored using a mouse model of acute alcohol-induced liver injury. AC contained 25 types of fatty acid, 16 types of amino acid, 3 types of nucleotide, and 8 types of mineral. The hepatoprotective effects were observed after 2 weeks of AC treatment at doses of 75 mg/kg, 225 mg/kg, and 675 mg/kg in the mouse model. These effects were indicated by the changes in the levels of aspartate aminotransferase, alanine aminotransferase, several oxidation-related factors, and inflammatory cytokines in serum and/or liver samples. AC reduced the incidence rate of necrosis, inflammatory infiltration, fatty droplets formation, and cell apoptosis in liver detecting via histological and TUNEL assay. In addition, AC reduced the expression of cleaved caspase-3, -8, and -9 and the levels of phosphor-protein kinase B (Akt) and phosphor-nuclear factor-κB (NF-κB) in the liver samples. Collectively, AC-mediated hepatoprotective effects in a mouse model of acute alcohol-induced liver injury are the result of reduction in oxidative stress. This may be associated with Akt/NF-κB signaling. These results provide valuable evidence to support the use of A. cinnamomea as a functional food and/or medicine.

Aspalathin Protects the Heart against Hyperglycemia-Induced Oxidative Damage by Up-Regulating Nrf2 Expression

Aspalathin (ASP) can protect H9c2 cardiomyocytes against high glucose (HG)-induced shifts in myocardial substrate preference, oxidative stress, and apoptosis. The protective mechanism of ASP remains unknown. However, as one of possible, it is well known that phytochemical flavonoids reduce oxidative stress via nuclear factor (erythroid-derived 2)-like 2 (Nrf2) activation resulting in up-regulation of antioxidant genes and enzymes. Therefore, we hypothesized that ASP protects the myocardium against HG- and hyperglycemia-induced oxidative damage by up-regulating Nrf2 expression in H9c2 cardiomyocytes and diabetic (db/db) mice, respectively. Using an oxidative stress RT² Profiler PCR array, ASP at a dose of 1 µM was demonstrated to protect H9c2 cardiomyocytes against HG-induced oxidative stress, but silencing of Nrf2 abolished this protective response of ASP and exacerbated cardiomyocyte apoptosis. Db/db mice and their non-diabetic (db/+) littermate controls were subsequently treated daily for six weeks with either a low (13 mg/kg) or high (130 mg/kg) ASP dose. Compared to nondiabetic mice the db/db mice presented increased cardiac remodeling and enlarged left ventricular wall that occurred concomitant to enhanced oxidative stress. Daily treatment of mice with ASP at a dose of 130 mg/kg for six weeks was more effective at reversing complications than both a low dose ASP or metformin, eliciting enhanced expression of Nrf2 and its downstream antioxidant genes. These results indicate that ASP maintains cellular homeostasis and protects the myocardium against hyperglycemia-induced oxidative stress through activation of Nrf2 and its downstream target genes.

d,l-Sulforaphane Induces ROS-Dependent Apoptosis in Human Gliomablastoma Cells by Inactivating STAT3 Signaling Pathway

d,l-Sulforaphane (SFN), a synthetic analogue of broccoli-derived isomer l-SFN, exerts cytotoxic effects on multiple tumor cell types through different mechanisms and is more potent than the l-isomer at inhibiting cancer growth. However, the means by which SFN impairs glioblastoma (GBM) cells remains poorly understood. In this study, we investigated the anti-cancer effect of SFN in GBM cells and determined the underlying molecular mechanisms. Cell viability assays, flow cytometry, immunofluorescence, and Western blot results revealed that SFN could induced apoptosis of GBM cells in a dose- and time-dependent manner, via up-regulation of caspase-3 and Bax, and down-regulation of Bcl-2. Mechanistically, SFN treatment led to increase the intracellular reactive oxygen species (ROS) level in GBM cells. Meanwhile, SFN also suppressed both constitutive and IL-6-induced phosphorylation of STAT3, and the activation of upstream JAK2 and Src tyrosine kinases, dose- and time-dependently. Moreover, blockage of ROS production by using the ROS inhibitor N-acetyl-l-cysteine totally reversed SFN-mediated down-regulation of JAK2/Src-STAT3 signaling activation and the subsequent effects on apoptosis by blocking the induction of apoptosis-related genes in GBM cells. Taken together, our data suggests that SFN induces apoptosis in GBM cells via ROS-dependent inactivation of STAT3 phosphorylation. These findings motivate further evaluation of SFN as a cancer chemopreventive agent in GBM treatment.

Development, Prevention, and Treatment of Alcohol-Induced Organ Injury: The Role of Nutrition

Alcohol and nutrition have the potential to interact at multiple levels. For example, heavy alcohol consumption can interfere with normal nutrition, resulting in overall malnutrition or in deficiencies of important micronutrients, such as zinc, by reducing their absorption or increasing their loss. Interactions between alcohol consumption and nutrition also can affect epigenetic regulation of gene expression by influencing multiple regulatory mechanisms, including methylation and acetylation of histone proteins and DNA. These effects may contribute to alcohol-related organ or tissue injury. The impact of alcohol-nutrition interactions has been assessed for several organs and tissues, including the intestine, where heavy alcohol use can increase intestinal permeability, and the liver, where the degree of malnutrition can be associated with the severity of liver injury and liver disease. Alcohol-nutrition interactions also play a role in alcohol-related lung injury, brain injury, and immune dysfunction. Therefore, treatment involving nutrient supplementation (e.g., with zinc or S-adenosylmethionine) may help prevent or attenuate some types of alcohol-induced organ damage.

Sulforaphane Improves Ischemia-Induced Detrusor Overactivity by Downregulating the Enhancement of Associated Endoplasmic Reticulum Stress, Autophagy, and Apoptosis in Rat Bladder

Atherosclerosis-associated pelvic ischemia has been reported to be a risk factor for bladder dysfunction and subsequent lower urinary tract symptoms (LUTS) in the elderly population. However, the molecular mechanisms of this association remain unclear. We hypothesized that stress-induced cellular responses might play a role in the pathogenesis of ischemia-induced bladder dysfunction. In the present study, the animal model of bladder ischemia was induced by bilateral partial arterial occlusion (BPAO) in rats. We found that BPAO significantly induced the presence of detrusor overactivity (DO) and upregulated the expression of several molecular reactions, including biomarkers in endoplasmic reticulum stress (78 kDa glucose-regulated protein, GRP78 and C/EBP-homologous protein, CHOP), autophagy (Beclin-1, p62 and LC3 II) and apoptosis (caspase 3). BPAO also disturbed the Kelch-like ECH-associated protein 1–nuclear factor erythroid-2-related factor 2 (Keap1–Nrf2) pathways. These responses might collectively alter muscarinic and purinergic signaling and contribute to the presence of DO in the ischemic bladder. Therapeutically, treatment with neither a muscarinic nor purinergic receptor antagonist restored bladder function. Interestingly, sulforaphane effectively attenuated ischemia-enhanced endoplasmic reticulum stress, autophagy and apoptosis in the bladder, subsequently ameliorated ischemia-induced bladder dysfunction and might emerge as a novel strategy to protect the bladder against ischemia-induced oxidative damage.

HPLC-based kinetics assay facilitates analysis of systems with multiple reaction products and thermal enzyme denaturation

Glucosinolates are plant secondary metabolites abundant in Brassica vegetables that are substrates for the enzyme myrosinase, a thioglucoside hydrolase. Enzyme-mediated hydrolysis of glucosinolates forms several organic products, including isothiocyanates (ITCs) that have been explored for their beneficial effects in humans. Myrosinase has been shown to be tolerant of non-natural glucosinolates, such as 2,2-diphenylethyl glucosinolate, and can facilitate their conversion to non-natural ITCs, some of which are leads for drug development. An HPLC-based method capable of analyzing this transformation for non-natural systems has been described. This current study describes (1) the Michaelis-Menten characterization of 2,2-diphenyethyl glucosinolate and (2) a parallel evaluation of this analogue and the natural analogue glucotropaeolin to evaluate effects of pH and temperature on rates of hydrolysis and product(s) formed. Methods described in this study provide the ability to simultaneously and independently analyze the kinetics of multiple reaction components. An unintended outcome of this work was the development of a modified Lambert W(x) which includes a parameter to account for the thermal denaturation of enzyme. The results of this study demonstrate that the action of Sinapis alba myrosinase on natural and non-natural glucosinolates is consistent under the explored range of experimental conditions and in relation to previous accounts.

Salvianolic Acid B Prevents Iodinated Contrast Media-Induced Acute Renal Injury in Rats via the PI3K/Akt/Nrf2 Pathway

Contrast-induced acute renal injury (CI-AKI) has become a common cause of hospital-acquired renal failure. However, the development of prophylaxis strategies and approved therapies for CI-AKI is limited. Salvianolic acid B (SB) can treat cardiovascular-related diseases. The aim of the present study was to assess the effect of SB on prevention of CI-AKI and explore its underlying mechanisms. We examined its effectiveness of preventing renal injury in a novel CI-AKI rat model. Compared with saline, intravenous SB pretreatment significantly attenuated elevations in serum creatinine and the histological changes of renal tubular injuries, reduced the number of apoptosis-positive tubular cells, activated Nrf2, and lowered the levels of renal oxidative stress induced by iodinated contrast media. The above renoprotection of SB was abolished by the PI3K inhibitor (wortmannin). In HK-2 cells, SB activated Nrf2 and decreased the levels of oxidative stress induced by hydrogen peroxide and subsequently improved cell viability. The above cytoprotection of SB was blocked by the PI3K inhibitor (wortmannin) or siNrf2. Thus, our results demonstrate that, due to its antioxidant properties, SB has the potential to effectively prevent CI-AKI via the PI3K/Akt/Nrf2 pathway.

Up-regulation of Siah1 by ethanol triggers apoptosis in neural crest cells through p38 MAPK-mediated activation of p53 signaling pathway

Seven in absentia homolog 1 (Siah1) is one of the E3 ubiquitin ligases and plays a key role in regulating target protein degradation. This study was designed to test the hypothesis that Siah1 mediates ethanol-induced apoptosis in NCCs through p38 MAPK-mediated activation of the p53 signaling pathway. We found that exposure of NCCs to ethanol resulted in the increases in the total protein levels of p53 and the phosphorylation of p53 at serine 15. Ethanol exposure also resulted in a significant increase in the phosphorylation of p38 MAPK. Knock-down of Siah1 dramatically reduced the ethanol-induced increase in the phosphorylation of p38 MAPK. Knock-down of Siah1 by siRNA or down-regulation of p38 MAPK by either siRNA or inhibitor significantly diminished ethanol-induced accumulations of p53 and the phosphorylation of p53. In addition, ethanol exposure resulted in a significant increase in the expression of p53 downstream targets and apoptosis in NCCs, which can be significantly diminished by down-regulation of Siah1 with siRNA. Knock-down of p38 MAPK by siRNA also dramatically reduced the ethanol-induced apoptosis. These results demonstrate that Siah1 plays a crucial role in ethanol-induced apoptosis in NCCs, and that the up-regulation of Siah1 by ethanol can trigger apoptosis through p38 MAPK-mediated activation of the p53 signaling pathway.

Tert-butylhydroquinone attenuates the ethanol-induced apoptosis of and activates the Nrf2 antioxidant defense pathway in H9c2 cardiomyocytes

Tert-butylhydroquinone (tBHQ), an inducer of nuclear factor erythroid 2-related factor 2 (Nrf2), has been demonstrated to attenuate oxidative stress-induced injury and the apoptosis of human neural stem cells and other cell types. However, whether tBHQ is able to exert a protective effect against oxidative stress and the apoptosis of cardiomyocytes has not yet been determined. Thus, the objective of the present study was to determine whether tBHQ protects H9c2 cardiomyocytes against ethanol-induced apoptosis. For this purpose, four sets of experiments were performed under standard culture conditions as follows: i) untreated control cells; ii) cell treatment with 200 mM ethanol; iii) cell treatment with 5 µM tBHQ; and iv) cell pre-treatment with 5 µM tBHQ for 24 h, followed by medium change and co-culture with 200 mM ethanol containing 5 µM tBHQ for a further 24 h. The viability of the cardiomyocytes was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of intracellular reactive oxygen species (ROS) and apoptosis were assessed by flow cytometry. Protein expression was measured by western blot analysis, and Nrf2 nuclear localization was observed by immunofluorescence. Exposure to ethanol led to a decrease in the protein expression of Nrf2 and its downstream antioxidant enzymes, accompanied by an increase in ROS generation and in the apoptosis of H9c2 cells. Pre-treatment with tBHQ significantly prevented the H9c2 cells from undergoing ethanol-induced apoptosis. tBHQ also increased the expression of B-cell lymphoma-2 (Bcl-2), whereas Bcl-2-associated X protein (Bax) expression was decreased. tBHQ promoted Nrf2 nuclear localization and increased the expression of Nrf2, superoxide dismutase (SOD), catalase (CAT) and heme oxygenase-1 (HO-1), and simultaneously inhibited the ethanol-induced overproduction of intracellular ROS. Therefore, tBHQ confers protection against the ethanol-induced apoptosis of and activates the Nrf2 antioxidant pathway in H9c2 cardiomyocytes.

Sulforaphane Suppresses Hepatitis C Virus Replication by Up-Regulating Heme Oxygenase-1 Expression through PI3K/Nrf2 Pathway

Hepatitis C virus (HCV) infection-induced oxidative stress is a major risk factor for the development of HCV-associated liver disease. Sulforaphane (SFN) is an antioxidant phytocompound that acts against cellular oxidative stress and tumorigenesis. However, there is little known about its anti-viral activity. In this study, we demonstrated that SFN significantly suppressed HCV protein and RNA levels in HCV replicon cells and infectious system, with an IC50 value of 5.7 ± 0.2 μM. Moreover, combination of SFN with anti-viral drugs displayed synergistic effects in the suppression of HCV replication. In addition, we found nuclear factor erythroid 2-related factor 2 (Nrf2)/HO-1 induction in response to SFN and determined the signaling pathways involved in this process, including inhibition of NS3 protease activity and induction of IFN response. In contrast, the anti-viral activities were attenuated by knockdown of HO-1 with specific inhibitor (SnPP) and shRNA, suggesting that anti-HCV activity of SFN is dependent on HO-1 expression. Otherwise, SFN stimulated the phosphorylation of phosphoinositide 3-kinase (PI3K) leading Nrf2-mediated HO-1 expression against HCV replication. Overall, our results indicated that HO-1 is essential in SFN-mediated anti-HCV activity and provide new insights in the molecular mechanism of SFN in HCV replication.

Alcohol Upregulation of CYP2A5: Role of Reactive Oxygen Species

Hepatic cytochrome P450 (CYP) 2E1 and CYP2A5 activate many important drugs and hepatotoxins. CYP2E1 is induced by alcohol, but whether CYP2A5 is upregulated by alcohol is not known. This article reviews recent studies on the induction of CYP2A5 by alcohol and the mechanism and role of reactive oxygen species (ROS) in this upregulation. Chronic feeding of ethanol to wild type mice increased CYP2A5 catalytic activity and protein and mRNA levels. This induction was blunted in CYP2E1 knockout mice and by a CYP2E1 inhibitor, but was restored in CYP2E1 knockin mice, suggesting a role for CYP2E1 in the induction of CYP2A5 by alcohol. Since CYP2E1 actively generates ROS, the possible role of ROS in the induction of CYP2A5 by alcohol was determined. ROS production was elevated by ethanol treatment. The antioxidants N-acetyl cysteine and vitamin C lowered the alcohol-induced elevation of ROS and blunted the alcohol-mediated induction of CYP2A5. These results suggest that ROS play a novel role in the crosstalk between CYP2E1 and CYP2A5. Alcohol treatment activated nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2), a transcription factor which up-regulates expression of CYP2A5. The antioxidants blocked the activation of Nrf2. The alcohol-induced elevation of CYP2A5, but not CYP2E1, was lower in Nrf2 knockout mice. We propose that increased generation of ROS from the alcohol-induced CYP2E1 activates Nrf2, which subsequently up-regulates the expression of CYP2A5. Thus, a novel consequence of the alcohol-mediated induction of CYP2E1 and increase in ROS is the activation of redox-sensitive transcription factors, such as Nrf2, and expression of CYP2A5. Further perspectives on this alcohol-CYP2E1-ROS-Nrf2-CYP2A5 pathway are presented.

Sulforaphane Attenuates Contrast-Induced Nephropathy in Rats via Nrf2/HO-1 Pathway

Background. Oxidative stress plays an important role in the pathogenesis of contrast-induced nephropathy (CIN). The aim of this study was to investigate the antioxidant effects of sulforaphane (SFN) in a rat model of CIN and a cell model of oxidative stress in HK2 cells. Methods. Rats were randomized into four groups (n = 6 per group): control group, Ioversol group (Ioversol-induced CIN), Ioversol + SFN group (CIN rats pretreated with SFN), and SFN group (rats treated with SFN). Renal function tests, malondialdehyde (MDA), and reactive oxygen species (ROS) were measured. Western blot, real-time polymerase chain reaction analysis, and immunohistochemical analysis were performed for nuclear factor erythroid-derived 2-like 2 (Nrf2) and heme oxygenase-1 (HO-1) detection. Results. Serum blood urea nitrogen (BUN), creatinine, and renal tissue MDA were increased after contrast exposure. Serum BUN, creatinine, and renal tissue MDA were decreased in the Ioversol + SFN group as compared with those in the Ioversol group. SFN increased the expression of Nrf2 and HO-1 in CIN rats and in Ioversol-induced injury HK2 cells. SFN increased cell viability and attenuated ROS level in vitro. Conclusions. SFN attenuates experimental CIN in vitro and in vivo. This effect is suggested to activate the Nrf2 antioxidant defenses pathway.

Embryonic oxidative stress results in reproductive impairment for adult zebrafish

Exposure to environmental stressors during embryo development can have long-term effects on the adult organism. This study used the thioredoxin reductase inhibitor auranofin to investigate the consequences of oxidative stress during zebrafish development. Auranofin at low doses triggered upregulation of the antioxidant genes gstp1 and prdx1. As the dose was increased, acute developmental abnormalities, including cerebral hemorrhaging and jaw malformation, were observed. To determine whether transient disruption of redox homeostasis during development could have long-term consequences, zebrafish embryos were exposed to a low dose of auranofin from 6–24 hours post fertilization, and then raised to adulthood. The adult fish were outwardly normal in their appearance with no gross physical differences compared to the control group. However, these adult fish had reduced odds of breeding and a lower incidence of egg fertilization. This study shows that a suboptimal early life environment can reduce the chances of reproductive success in adulthood.

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We exposed zebrafish embryos to the oxidative stress-inducing compound auranofin.

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Embryos showed a dose-dependent increase in developmental abnormalities.

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Exposed embryos responded by upregulating oxidative stress-responsive genes.

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Embryos transiently exposed to a low dose of auranofin were raised into adults.

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The resulting adults had reduced fertility compared with controls.